Custom TimeSpan Format Strings

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A TimeSpan format string defines the string representation of a TimeSpan value that results from a formatting operation. A custom format string consists of one or more custom TimeSpan format specifiers along with any number of literal characters. Any string that is not a standard TimeSpan format string is interpreted as a custom TimeSpan format string.

Important noteImportant Note:

The custom TimeSpan format specifiers do not include placeholder separator symbols, such as the symbols that separate days from hours, hours from minutes, or seconds from fractional seconds. Instead, these symbols must be included in the custom format string as string literals. For example, "dd\.hh\:mm" defines a period (.) as the separator between days and hours, and a colon (:) as the separator between hours and minutes.

The string representations of TimeSpan values are produced by calls to the overloads of the TimeSpan.ToString method, and by methods that support composite formatting, such as String.Format. For more information, see Formatting Types and Composite Formatting. The following example illustrates the use of custom format strings in formatting operations.

Module Example
   Public Sub Demo(outputBlock As System.Windows.Controls.TextBlock)
      Dim duration As New TimeSpan(1, 12, 23, 62)

      Dim output As String = Nothing
      output = "Time of Travel: " + duration.ToString("%d") + " days"
      outputBlock.Text += output + vbCrLf
      output = "Time of Travel: " + duration.ToString("dd\.hh\:mm\:ss") 
      outputBlock.Text += output + vbCrLf

      outputBlock.Text += String.Format("Time of Travel: {0:%d} day(s)", 
                                        duration) + vbCrLf
      outputBlock.Text += String.Format("Time of Travel: {0:dd\.hh\:mm\:ss} days", 
                                        duration) + vbCrLf
   End Sub
End Module
' The example displays the following output:
'       Time of Travel: 1 days
'       Time of Travel: 01.12:24:02
'       Time of Travel: 1 day(s)
'       Time of Travel: 01.12:24:02 days
using System;

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      TimeSpan duration = new TimeSpan(1, 12, 23, 62);

      string output = null;
      output = "Time of Travel: " + duration.ToString("%d") + " days";
      outputBlock.Text += output + Environment.NewLine;
      output = "Time of Travel: " + duration.ToString(@"dd\.hh\:mm\:ss"); 
      outputBlock.Text += output + Environment.NewLine;

      outputBlock.Text += String.Format("Time of Travel: {0:%d} day(s)", 
                                        duration) + Environment.NewLine;
      outputBlock.Text += String.Format("Time of Travel: {0:dd\\.hh\\:mm\\:ss} days", 
                                        duration) + Environment.NewLine;
   }
}
// The example displays the following output:
//       Time of Travel: 1 days
//       Time of Travel: 01.12:24:02
//       Time of Travel: 1 day(s)
//       Time of Travel: 01.12:24:02 days

Custom TimeSpan format strings are also used by the TimeSpan.ParseExact and TimeSpan.TryParseExact methods to define the required format of input strings for parsing operations. (Parsing converts the string representation of a value to that value.) The following example illustrates the use of standard format strings in parsing operations.

Module Example
   Public Sub Demo(outputBlock As System.Windows.Controls.TextBlock)
      Dim value As String = Nothing
      Dim interval As TimeSpan

      value = "6"
      If TimeSpan.TryParseExact(value, "%d", Nothing, interval) Then
         outputBlock.Text += String.Format("{0} --> {1}", value, interval.ToString("c")) + vbCrLf
      Else
         outputBlock.Text += String.Format("Unable to parse '{0}'", value) + vbCrLf
      End If

      value = "16:32.05"
      If TimeSpan.TryParseExact(value, "mm\:ss\.ff", Nothing, interval) Then
         outputBlock.Text += String.Format("{0} --> {1}", value, interval.ToString("c")) + vbCrLf
      Else
         outputBlock.Text += String.Format("Unable to parse '{0}'", value) + vbCrLf
      End If

      value= "12.035"
      If TimeSpan.TryParseExact(value, "ss\.fff", Nothing, interval) Then
         outputBlock.Text += String.Format("{0} --> {1}", value, interval.ToString("c")) + vbCrLf
      Else
         outputBlock.Text += String.Format("Unable to parse '{0}'", value) + vbCrLf
      End If
   End Sub
End Module
' The example displays the following output:
'       6 --> 6.00:00:00
'       16:32.05 --> 00:16:32.0500000
'       12.035 --> 00:00:12.0350000
using System;

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      string value = null;
      TimeSpan interval;

      value = "6";
      if (TimeSpan.TryParseExact(value, "%d", null, out interval))
         outputBlock.Text += String.Format("{0} --> {1}", value, 
                                           interval.ToString("c")) + Environment.NewLine;
      else
         outputBlock.Text += String.Format("Unable to parse '{0}'", value) + Environment.NewLine;

      value = "16:32.05";
      if (TimeSpan.TryParseExact(value, @"mm\:ss\.ff", null, out interval))
         outputBlock.Text += String.Format("{0} --> {1}", value, 
                                           interval.ToString("c")) + Environment.NewLine;
      else
         outputBlock.Text += String.Format("Unable to parse '{0}'", value) + Environment.NewLine;

      value= "12.035";
      if (TimeSpan.TryParseExact(value, "ss\\.fff", null, out interval))
         outputBlock.Text += String.Format("{0} --> {1}", value, 
                                           interval.ToString("c")) + Environment.NewLine;
      else
         outputBlock.Text += String.Format("Unable to parse '{0}'", value) + Environment.NewLine;
   }
}
// The example displays the following output:
//       6 --> 6.00:00:00
//       16:32.05 --> 00:16:32.0500000
//       12.035 --> 00:00:12.0350000

The following table describes the custom date and time format specifiers.

Format specifier

Description

Example

"d", "%d"

The number of whole days in the time interval.

More information: The "d" Custom Format Specifier.

new TimeSpan(6, 14, 32, 17, 685):

   %d --> "6"

   d\.hh\:mm --> "6.14:32"

"dd"-"dddddddd"

The number of whole days in the time interval, padded with leading zeros as needed.

More information: The "dd"-"dddddddd" Custom Format Specifiers.

new TimeSpan(6, 14, 32, 17, 685):

   ddd --> "006"

   dd\.hh\:mm --> "06.14:32"

"h", "%h"

The number of whole hours in the time interval that are not counted as part of days. Single-digit hours do not have a leading zero.

More information: The "h" Custom Format Specifier.

new TimeSpan(6, 14, 32, 17, 685):

   %h --> "14"

   hh\:mm --> "14:32"

"hh"

The number of whole hours in the time interval that are not counted as part of days. Single-digit hours have a leading zero.

More information: The "hh" Custom Format Specifier.

new TimeSpan(6, 14, 32, 17, 685):

   hh --> "14"

new TimeSpan(6, 8, 32, 17, 685):

   hh --> 08

"m", "%m"

The number of whole minutes in the time interval that are not included as part of hours or days. Single-digit minutes do not have a leading zero.

More information: The "m" Custom Format Specifier.

new TimeSpan(6, 14, 8, 17, 685):

   %m --> "8"

   h\:m --> "14:8"

"mm"

The number of whole minutes in the time interval that are not included as part of hours or days. Single-digit minutes have a leading zero.

More information: The "mm" Custom Format Specifier.

new TimeSpan(6, 14, 8, 17, 685):

   mm --> "08"

new TimeSpan(6, 8, 5, 17, 685):

   d\.hh\:mm\:ss --> 6.08:05:17

"s", "%s"

The number of whole seconds in the time interval that are not included as part of hours, days, or minutes. Single-digit seconds do not have a leading zero.

More information: The "s" Custom Format Specifier.

TimeSpan.FromSeconds(12.965):

   %s --> 12

   s\.fff --> 12.965

"ss"

The number of whole seconds in the time interval that are not included as part of hours, days, or minutes. Single-digit seconds have a leading zero.

More information: The "ss" Custom Format Specifier.

TimeSpan.FromSeconds(6.965):

   ss --> 06

   ss\.fff --> 06.965

"f", "%f"

The tenths of a second in a time interval.

More information: The "f" Custom Format Specifier.

TimeSpan.FromSeconds(6.895):

   f --> 8

   ss\.f --> 06.8

"ff"

The hundredths of a second in a time interval.

More information: The "ff" Custom Format Specifier.

TimeSpan.FromSeconds(6.895):

   ff --> 89

   ss\.ff --> 06.89

"fff"

The milliseconds in a time interval.

More information: The "fff" Custom Format Specifier.

TimeSpan.FromSeconds(6.895):

   fff --> 895

   ss\.fff --> 06.895

"ffff"

The ten-thousandths of a second in a time interval.

More information: The "ffff" Custom Format Specifier.

TimeSpan.Parse("0:0:6.8954321"):

   ffff --> 8954

   ss\.ffff --> 06.8954

"fffff"

The hundred-thousandths of a second in a time interval.

More information: The "fffff" Custom Format Specifier.

TimeSpan.Parse("0:0:6.8954321"):

   fffff --> 89543

   ss\.fffff --> 06.89543

"ffffff"

The millionths of a second in a time interval.

More information: The "ffffff" Custom Format Specifier.

TimeSpan.Parse("0:0:6.8954321"):

   ffffff --> 895432

   ss\.ffffff --> 06.895432

"fffffff"

The ten-millionths of a second (or the fractional ticks) in a time interval.

More information: The "fffffff" Custom Format Specifier.

TimeSpan.Parse("0:0:6.8954321"):

   fffffff --> 8954321

   ss\.fffffff --> 06.8954321

"F", "%F"

The tenths of a second in a time interval. Nothing is displayed if the digit is zero.

More information: The "F" Custom Format Specifier.

TimeSpan.Parse("00:00:06.32"):

   %F: 3

TimeSpan.Parse("0:0:3.091"):

   ss\.F: 03.

"FF"

The hundredths of a second in a time interval. Any fractional trailing zeros or two zero digits are not included.

More information: The "FF" Custom Format Specifier.

TimeSpan.Parse("00:00:06.329"):

   FF: 32

TimeSpan.Parse("0:0:3.101"):

   ss\.FF: 03.1

"FFF"

The milliseconds in a time interval. Any fractional trailing zeros are not included.

More information:

TimeSpan.Parse("00:00:06.3291"):

   FFF: 329

TimeSpan.Parse("0:0:3.1009"):

   ss\.FFF: 03.1

"FFFF"

The ten-thousandths of a second in a time interval. Any fractional trailing zeros are not included.

More information: The "FFFF" Custom Format Specifier.

TimeSpan.Parse("00:00:06.32917"):

   FFFFF: 3291

TimeSpan.Parse("0:0:3.10009"):

   ss\.FFFF: 03.1

"FFFFF"

The hundred-thousandths of a second in a time interval. Any fractional trailing zeros are not included.

More information: The "FFFFF" Custom Format Specifier.

TimeSpan.Parse("00:00:06.329179"):

   FFFFF: 32917

TimeSpan.Parse("0:0:3.100009"):

   ss\.FFFFF: 03.1

"FFFFFF"

The millionths of a second in a time interval. Any fractional trailing zeros are not displayed.

More information: The "FFFFFF" Custom Format Specifier.

TimeSpan.Parse("00:00:06.3291791"):

   FFFFFF: 329179

TimeSpan.Parse("0:0:3.1000009"):

   ss\.FFFFFF: 03.1

"FFFFFFF"

The ten-millions of a second in a time interval. Any fractional trailing zeros or seven zeros are not displayed.

More information: The "FFFFFFF" Custom Format Specifier.

TimeSpan.Parse("00:00:06.3291791"):

   FFFFFF: 3291791

TimeSpan.Parse("0:0:3.1900000"):

   ss\.FFFFFF: 03.19

'string'

Literal string delimiter.

More information: Other Characters.

new TimeSpan(14, 32, 17):

   hh':'mm':'ss --> "14:32:17"

\

The escape character.

More information: Other Characters.

new TimeSpan(14, 32, 17):

   hh\:mm\:ss --> "14:32:17"

Any other character

Any other unescaped character is interpreted as a custom format specifier.

More Information: Other Characters.

new TimeSpan(14, 32, 17):

   hh\:mm\:ss --> "14:32:17"

The "d" Custom Format Specifier

The "d" custom format specifier outputs the value of the TimeSpan.Days property, which represents the number of whole days in the time interval. It outputs the full number of days in a TimeSpan value, even if the value has more than one digit. If the value of the TimeSpan.Days property is zero, the specifier outputs "0".

If the "d" custom format specifier is used alone, specify "%d" so that it is not misinterpreted as a standard format string. The following example provides an illustration.

Dim ts As New TimeSpan(16, 4, 3, 17, 250)
outputBlock.Text += ts.ToString("%d") + vbCrLf
' Displays 16   
TimeSpan ts1 = new TimeSpan(16, 4, 3, 17, 250);
outputBlock.Text += ts1.ToString("%d") + Environment.NewLine;
// Displays 16   

The following example illustrates the use of the "d" custom format specifier.

Dim ts2 As New TimeSpan(4, 3, 17)
outputBlock.Text += ts2.ToString("d\.hh\:mm\:ss") + vbCrLf

Dim ts3 As New TimeSpan(3, 4, 3, 17)
outputBlock.Text += ts3.ToString("d\.hh\:mm\:ss") + vbCrLf
' The example displays the following output:
'       0.04:03:17
'       3.04:03:17      
TimeSpan ts2 = new TimeSpan(4, 3, 17);
outputBlock.Text += ts2.ToString(@"d\.hh\:mm\:ss") + Environment.NewLine;

TimeSpan ts3 = new TimeSpan(3, 4, 3, 17);
outputBlock.Text += ts3.ToString(@"d\.hh\:mm\:ss") + Environment.NewLine;
// The example displays the following output:
//       0.04:03:17
//       3.04:03:17      

Back to table

The "dd"-"dddddddd" Custom Format Specifiers

The "dd", "ddd", "dddd", "ddddd", "dddddd", "ddddddd", and "dddddddd" custom format specifiers output the value of the TimeSpan.Days property, which represents the number of whole days in the time interval.

The output string includes a minimum number of digits specified by the number of "d" characters in the format specifier, and it is padded with leading zeros as needed. If the digits in the number of days exceed the number of "d" characters in the format specifier, the full number of days is output in the result string.

The following example uses these format specifiers to display the string representation of two TimeSpan values. The value of the days component of the first time interval is zero; the value of the days component of the second is 365.

Dim ts1 As New TimeSpan(0, 23, 17, 47)
Dim ts2 As New TimeSpan(365, 21, 19, 45)

For ctr As Integer = 2 To 8
   Dim fmt As String = New String("d"c, ctr) + "\.hh\:mm\:ss"
   outputBlock.Text += String.Format("{0} --> {1:" + fmt + "}", fmt, ts1) + vbCrLf 
   outputBlock.Text += String.Format("{0} --> {1:" + fmt + "}", fmt, ts2) + vbCrLf 
   outputBlock.Text += vbCrLf
Next  
' The example displays the following output:
'       dd\.hh\:mm\:ss --> 00.23:17:47
'       dd\.hh\:mm\:ss --> 365.21:19:45
'       
'       ddd\.hh\:mm\:ss --> 000.23:17:47
'       ddd\.hh\:mm\:ss --> 365.21:19:45
'       
'       dddd\.hh\:mm\:ss --> 0000.23:17:47
'       dddd\.hh\:mm\:ss --> 0365.21:19:45
'       
'       ddddd\.hh\:mm\:ss --> 00000.23:17:47
'       ddddd\.hh\:mm\:ss --> 00365.21:19:45
'       
'       dddddd\.hh\:mm\:ss --> 000000.23:17:47
'       dddddd\.hh\:mm\:ss --> 000365.21:19:45
'       
'       ddddddd\.hh\:mm\:ss --> 0000000.23:17:47
'       ddddddd\.hh\:mm\:ss --> 0000365.21:19:45
'       
'       dddddddd\.hh\:mm\:ss --> 00000000.23:17:47
'       dddddddd\.hh\:mm\:ss --> 00000365.21:19:45      
TimeSpan ts1 = new TimeSpan(0, 23, 17, 47);
TimeSpan ts2 = new TimeSpan(365, 21, 19, 45);

for (int ctr = 2; ctr <= 8; ctr++)
{
   string fmt = new String('d', ctr) + @"\.hh\:mm\:ss";
   outputBlock.Text += String.Format("{0} --> {1:" + fmt + "}", fmt, ts1) + Environment.NewLine;  
   outputBlock.Text += String.Format("{0} --> {1:" + fmt + "}", fmt, ts2) + Environment.NewLine;
   outputBlock.Text +=  Environment.NewLine;
}  
// The example displays the following output:
//       dd\.hh\:mm\:ss --> 00.23:17:47
//       dd\.hh\:mm\:ss --> 365.21:19:45
//       
//       ddd\.hh\:mm\:ss --> 000.23:17:47
//       ddd\.hh\:mm\:ss --> 365.21:19:45
//       
//       dddd\.hh\:mm\:ss --> 0000.23:17:47
//       dddd\.hh\:mm\:ss --> 0365.21:19:45
//       
//       ddddd\.hh\:mm\:ss --> 00000.23:17:47
//       ddddd\.hh\:mm\:ss --> 00365.21:19:45
//       
//       dddddd\.hh\:mm\:ss --> 000000.23:17:47
//       dddddd\.hh\:mm\:ss --> 000365.21:19:45
//       
//       ddddddd\.hh\:mm\:ss --> 0000000.23:17:47
//       ddddddd\.hh\:mm\:ss --> 0000365.21:19:45
//       
//       dddddddd\.hh\:mm\:ss --> 00000000.23:17:47
//       dddddddd\.hh\:mm\:ss --> 00000365.21:19:45      

Back to table

The "h" Custom Format Specifier

The "h" custom format specifier outputs the value of the TimeSpan.Hours property, which represents the number of whole hours in the time interval that is not counted as part of its day component. It returns a one-digit string value if the value of the TimeSpan.Hours property is 0 through 9, and it returns a two-digit string value if the value of the TimeSpan.Hours property ranges from 10 to 23.

If the "h" custom format specifier is used alone, specify "%h" so that it is not misinterpreted as a standard format string. The following example provides an illustration.

Dim ts As New TimeSpan(3, 42, 0)
outputBlock.Text += String.Format("{0:%h} hours {0:%m} minutes", ts) + vbCrLf
' The example displays the following output:
'       3 hours 42 minutes
TimeSpan ts = new TimeSpan(3, 42, 0);
outputBlock.Text += String.Format("{0:%h} hours {0:%m} minutes", ts) + Environment.NewLine;
// The example displays the following output:
//       3 hours 42 minutes

Ordinarily, in a parsing operation, an input string that includes only a single number is interpreted as the number of days. You can use the "%h" custom format specifier instead to interpret the numeric string as the number of hours. The following example provides an illustration.

Dim value As String = "8"
Dim interval As TimeSpan
If TimeSpan.TryParseExact(value, "%h", Nothing, interval) Then
   outputBlock.Text += interval.ToString("c") + vbCrLf
Else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                     value) + vbCrLf   
End If   
' The example displays the following output:
'       08:00:00                              
string value = "8";
TimeSpan interval;
if (TimeSpan.TryParseExact(value, "%h", null, out interval))
   outputBlock.Text += interval.ToString("c") + Environment.NewLine;
else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                     value) + Environment.NewLine;   
// The example displays the following output:
//       08:00:00                              

The following example illustrates the use of the "h" custom format specifier.

Dim ts1 As New TimeSpan(14, 3, 17)
outputBlock.Text += ts1.ToString("d\.h\:mm\:ss") + vbCrLf

Dim ts2 As New TimeSpan(3, 4, 3, 17)
outputBlock.Text += ts2.ToString("d\.h\:mm\:ss") + vbCrLf
' The example displays the following output:
'       0.14:03:17
'       3.4:03:17
TimeSpan ts1 = new TimeSpan(14, 3, 17);
outputBlock.Text += ts1.ToString(@"d\.h\:mm\:ss") + Environment.NewLine;

TimeSpan ts2 = new TimeSpan(3, 4, 3, 17);
outputBlock.Text += ts2.ToString(@"d\.h\:mm\:ss") + Environment.NewLine;
// The example displays the following output:
//       0.14:03:17
//       3.4:03:17

Back to table

The "hh" Custom Format Specifier

The "hh" custom format specifier outputs the value of the TimeSpan.Hours property, which represents the number of whole hours in the time interval that is not counted as part of its day component. For values from 0 through 9, the output string includes a leading zero.

Ordinarily, in a parsing operation, an input string that includes only a single number is interpreted as the number of days. You can use the "hh" custom format specifier instead to interpret the numeric string as the number of hours. The following example provides an illustration.

Dim value As String = "08"
Dim interval As TimeSpan
If TimeSpan.TryParseExact(value, "hh", Nothing, interval) Then
   outputBlock.Text += interval.ToString("c") + vbCrLf
Else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                     value) + vbCrLf   
End If   
' The example displays the following output:
'       08:00:00                              
string value = "08";
TimeSpan interval;
if (TimeSpan.TryParseExact(value, "hh", null, out interval))
   outputBlock.Text += interval.ToString("c") + Environment.NewLine;
else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                     value) + Environment.NewLine;   
// The example displays the following output:
//       08:00:00                              

The following example illustrates the use of the "hh" custom format specifier.

Dim ts1 As New TimeSpan(14, 3, 17)
outputBlock.Text += ts1.ToString("d\.hh\:mm\:ss") + vbCrLf

Dim ts2 As New TimeSpan(3, 4, 3, 17)
outputBlock.Text += ts2.ToString("d\.hh\:mm\:ss") + vbCrLf
' The example displays the following output:
'       0.14:03:17
'       3.04:03:17
TimeSpan ts1 = new TimeSpan(14, 3, 17);
outputBlock.Text += ts1.ToString(@"d\.hh\:mm\:ss") + Environment.NewLine;

TimeSpan ts2 = new TimeSpan(3, 4, 3, 17);
outputBlock.Text += ts2.ToString(@"d\.hh\:mm\:ss") + Environment.NewLine;
// The example displays the following output:
//       0.14:03:17
//       3.04:03:17

Back to table

The "m" Custom Format Specifier

The "m" custom format specifier outputs the value of the TimeSpan.Minutes property, which represents the number of whole minutes in the time interval that is not counted as part of its day component. It returns a one-digit string value if the value of the TimeSpan.Minutes property is 0 through 9, and it returns a two-digit string value if the value of the TimeSpan.Minutes property ranges from 10 to 59.

If the "m" custom format specifier is used alone, specify "%m" so that it is not misinterpreted as a standard format string. The following example provides an illustration.

Dim ts As New TimeSpan(3, 42, 0)
outputBlock.Text += String.Format("{0:%h} hours {0:%m} minutes", ts) + vbCrLf
' The example displays the following output:
'       3 hours 42 minutes
TimeSpan ts = new TimeSpan(3, 42, 0);
outputBlock.Text += String.Format("{0:%h} hours {0:%m} minutes", ts) + Environment.NewLine;
// The example displays the following output:
//       3 hours 42 minutes

Ordinarily, in a parsing operation, an input string that includes only a single number is interpreted as the number of days. You can use the "%m" custom format specifier instead to interpret the numeric string as the number of minutes. The following example provides an illustration.

Dim value As String = "3"
Dim interval As TimeSpan
If TimeSpan.TryParseExact(value, "%m", Nothing, interval) Then
   outputBlock.Text += interval.ToString("c") + vbCrLf
Else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                     value) + vbCrLf   
End If   
' The example displays the following output:
'       00:03:00                              
string value = "3";
TimeSpan interval;
if (TimeSpan.TryParseExact(value, "%m", null, out interval))
   outputBlock.Text += interval.ToString("c") + Environment.NewLine;
else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                     value) + Environment.NewLine;   
// The example displays the following output:
//       00:03:00                              

The following example illustrates the use of the "m" custom format specifier.

Dim ts1 As New TimeSpan(0, 6, 32)
outputBlock.Text += String.Format("{0:m\:ss} minutes", ts1) + vbCrLf

Dim ts2 As New TimeSpan(0, 18, 44)
outputBlock.Text += String.Format("Elapsed time: {0:m\:ss}", ts2) + vbCrLf
' The example displays the following output:
'       6:32 minutes
'       Elapsed time: 18:44
TimeSpan ts1 = new TimeSpan(0, 6, 32);
outputBlock.Text += String.Format("{0:m\\:ss} minutes", ts1) + Environment.NewLine;

TimeSpan ts2 = new TimeSpan(3, 4, 3, 17);
outputBlock.Text += String.Format("Elapsed time: {0:m\\:ss}", ts2) + Environment.NewLine;
// The example displays the following output:
//       6:32 minutes
//       Elapsed time: 18:44

Back to table

The "mm" Custom Format Specifier

The "mm" custom format specifier outputs the value of the TimeSpan.Minutes property, which represents the number of whole minutes in the time interval that is not included as part of its hours or days component. For values from 0 through 9, the output string includes a leading zero.

Ordinarily, in a parsing operation, an input string that includes only a single number is interpreted as the number of days. You can use the "mm" custom format specifier instead to interpret the numeric string as the number of minutes. The following example provides an illustration.

Dim value As String = "05"
Dim interval As TimeSpan
If TimeSpan.TryParseExact(value, "mm", Nothing, interval) Then
   outputBlock.Text += interval.ToString("c") + vbCrLf
Else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                       value) + vbCrLf   
End If   
' The example displays the following output:
'       00:05:00           
string value = "07";
TimeSpan interval;
if (TimeSpan.TryParseExact(value, "mm", null, out interval))
   outputBlock.Text += interval.ToString("c") + Environment.NewLine;
else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                     value) + Environment.NewLine;   
// The example displays the following output:
//       00:07:00                              

The following example illustrates the use of the "mm" custom format specifier.

Dim departTime As New TimeSpan(11, 12, 00)
Dim arriveTime As New TimeSpan(16, 28, 00)
outputBlock.Text += String.Format("Travel time: {0:hh\:mm}", 
                                  arriveTime - departTime) + vbCrLf
' The example displays the following output:
'       Travel time: 05:16      
TimeSpan departTime = new TimeSpan(11, 12, 00);
TimeSpan arriveTime = new TimeSpan(16, 28, 00);
outputBlock.Text += String.Format("Travel time: {0:hh\\:mm}", 
                                  arriveTime - departTime) + Environment.NewLine;
// The example displays the following output:
//       Travel time: 05:16      

Back to table

The "s" Custom Format Specifier

The "s" custom format specifier outputs the value of the TimeSpan.Seconds property, which represents the number of whole seconds in the time interval that is not included as part of its hours, days, or minutes component. It returns a one-digit string value if the value of the TimeSpan.Seconds property is 0 through 9, and it returns a two-digit string value if the value of the TimeSpan.Seconds property ranges from 10 to 59.

If the "s" custom format specifier is used alone, specify "%s" so that it is not misinterpreted as a standard format string. The following example provides an illustration.

Dim ts As TimeSpan = TimeSpan.FromSeconds(12.465)
outputBlock.Text += ts.ToString("%s") + vbCrLf
' The example displays the following output:
'       12
TimeSpan ts = TimeSpan.FromSeconds(12.465);
outputBlock.Text += ts.ToString("%s") + Environment.NewLine;
// The example displays the following output:
//       12

Ordinarily, in a parsing operation, an input string that includes only a single number is interpreted as the number of days. You can use the "%s" custom format specifier instead to interpret the numeric string as the number of seconds. The following example provides an illustration.

Dim value As String = "9"
Dim interval As TimeSpan
If TimeSpan.TryParseExact(value, "%s", Nothing, interval) Then
   outputBlock.Text += interval.ToString("c") + vbCrLf
Else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                     value) + vbCrLf   
End If   
' The example displays the following output:
'       00:00:09
string value = "9";
TimeSpan interval;
if (TimeSpan.TryParseExact(value, "%s", null, out interval))
   outputBlock.Text += interval.ToString("c") + Environment.NewLine;
else
   outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                     value) + Environment.NewLine;   
// The example displays the following output:
//       00:00:09

The following example illustrates the use of the "s" custom format specifier.

Dim startTime As New TimeSpan(0, 12, 30, 15, 0)
Dim endTime As New TimeSpan(0, 12, 30, 21, 3)
outputBlock.Text += String.Format("Elapsed Time: {0:s\:fff} seconds", 
                                  endTime - startTime) + vbCrLf
' The example displays the following output:
'       Elapsed Time: 6:003 seconds      
TimeSpan startTime = new TimeSpan(0, 12, 30, 15, 0);
TimeSpan endTime = new TimeSpan(0, 12, 30, 21, 3);
outputBlock.Text += String.Format(@"Elapsed Time: {0:s\:fff} seconds", 
                                  endTime - startTime) + Environment.NewLine;
// The example displays the following output:
//       Elapsed Time: 6:003 seconds      

Back to table

The "ss" Custom Format Specifier

The "ss" custom format specifier outputs the value of the TimeSpan.Seconds property, which represents the number of whole seconds in the time interval that is not included as part of its hours, days, or minutes component. For values from 0 through 9, the output string includes a leading zero.

Ordinarily, in a parsing operation, an input string that includes only a single number is interpreted as the number of days. You can use the "ss" custom format specifier instead to interpret the numeric string as the number of seconds. The following example provides an illustration.

Dim values() As String = { "49", "9", "06" }
Dim interval As TimeSpan
For Each value As String In values
   If TimeSpan.TryParseExact(value, "ss", Nothing, interval) Then
      outputBlock.Text += interval.ToString("c") + vbCrLf
   Else
      outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                        value) + vbCrLf   
   End If   
Next   
' The example displays the following output:
'       00:00:49
'       Unable to convert '9' to a time interval
'       00:00:06
string[] values = { "49", "9", "06" };
TimeSpan interval;
foreach (string value in values)
{
   if (TimeSpan.TryParseExact(value, "ss", null, out interval))
      outputBlock.Text += interval.ToString("c") + Environment.NewLine;
   else
      outputBlock.Text += String.Format("Unable to convert '{0}' to a time interval", 
                                        value) + Environment.NewLine;   
}
// The example displays the following output:
//       00:00:49
//       Unable to convert '9' to a time interval
//       00:00:06

The following example illustrates the use of the "ss" custom format specifier.

Dim interval1 As TimeSpan = TimeSpan.FromSeconds(12.60)
outputBlock.Text += interval1.ToString("ss\.fff") + vbCrLf
Dim interval2 As TimeSpan = TimeSpan.FromSeconds(6.485)
outputBlock.Text += interval2.ToString("ss\.fff") + vbCrLf
' The example displays the following output:
'       12.600
'       06.485
TimeSpan interval1 = TimeSpan.FromSeconds(12.60);
outputBlock.Text += interval1.ToString(@"ss\.fff") + Environment.NewLine;

TimeSpan interval2 = TimeSpan.FromSeconds(6.485);
outputBlock.Text += interval2.ToString(@"ss\.fff") + Environment.NewLine;
// The example displays the following output:
//       12.600
//       06.485

Back to table

The"f" Custom Format Specifier

The "f" custom format specifier outputs the tenths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the input string must contain exactly one fractional digit.

If the "f" custom format specifier is used alone, specify "%f" so that it is not misinterpreted as a standard format string.

The following example uses the "f" custom format specifier to display the tenths of a second in a TimeSpan value. "f" is used first as the only format specifier, and then combined with the "s" specifier in a custom format string.

Dim ts As New TimeSpan(1003498765432)
Dim fmt As String
outputBlock.Text += ts.ToString("c") + vbCrLf
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   If fmt.Length = 1 Then fmt = "%" + fmt
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", fmt, ts) + vbCrLf
Next 
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   outputBlock.Text += String.Format("{0,10}: {1:s\." + fmt + "}", "s\." + fmt, ts) + vbCrLf
Next
' The example displays the following output:
'            %f: 8
'            ff: 87
'           fff: 876
'          ffff: 8765
'         fffff: 87654
'        ffffff: 876543
'       fffffff: 8765432
'    
'           s\.f: 29.8
'          s\.ff: 29.87
'         s\.fff: 29.876
'        s\.ffff: 29.8765
'       s\.fffff: 29.87654
'      s\.ffffff: 29.876543
'     s\.fffffff: 29.8765432
TimeSpan ts = new TimeSpan(1003498765432);
string fmt;
outputBlock.Text += ts.ToString("c") + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   if (fmt.Length == 1) fmt = "%" + fmt;
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", 
                                     fmt, ts) + Environment.NewLine;
} 
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   outputBlock.Text += String.Format("{0,10}: {1:s\\." + fmt + "}", "s\\." + fmt, 
                                     ts) + Environment.NewLine;
}
// The example displays the following output:
//               %f: 8
//               ff: 87
//              fff: 876
//             ffff: 8765
//            fffff: 87654
//           ffffff: 876543
//          fffffff: 8765432
//       
//              s\.f: 29.8
//             s\.ff: 29.87
//            s\.fff: 29.876
//           s\.ffff: 29.8765
//          s\.fffff: 29.87654
//         s\.ffffff: 29.876543
//        s\.fffffff: 29.8765432      

Back to table

The "ff" Custom Format Specifier

The "ff" custom format specifier outputs the hundredths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the input string must contain exactly two fractional digits.

The following example uses the "ff" custom format specifier to display the hundredths of a second in a TimeSpan value. "ff" is used first as the only format specifier, and then combined with the "s" specifier in a custom format string.

Dim ts As New TimeSpan(1003498765432)
Dim fmt As String
outputBlock.Text += ts.ToString("c") + vbCrLf
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   If fmt.Length = 1 Then fmt = "%" + fmt
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", fmt, ts) + vbCrLf
Next 
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   outputBlock.Text += String.Format("{0,10}: {1:s\." + fmt + "}", "s\." + fmt, ts) + vbCrLf
Next
' The example displays the following output:
'            %f: 8
'            ff: 87
'           fff: 876
'          ffff: 8765
'         fffff: 87654
'        ffffff: 876543
'       fffffff: 8765432
'    
'           s\.f: 29.8
'          s\.ff: 29.87
'         s\.fff: 29.876
'        s\.ffff: 29.8765
'       s\.fffff: 29.87654
'      s\.ffffff: 29.876543
'     s\.fffffff: 29.8765432
TimeSpan ts = new TimeSpan(1003498765432);
string fmt;
outputBlock.Text += ts.ToString("c") + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   if (fmt.Length == 1) fmt = "%" + fmt;
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", 
                                     fmt, ts) + Environment.NewLine;
} 
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   outputBlock.Text += String.Format("{0,10}: {1:s\\." + fmt + "}", "s\\." + fmt, 
                                     ts) + Environment.NewLine;
}
// The example displays the following output:
//               %f: 8
//               ff: 87
//              fff: 876
//             ffff: 8765
//            fffff: 87654
//           ffffff: 876543
//          fffffff: 8765432
//       
//              s\.f: 29.8
//             s\.ff: 29.87
//            s\.fff: 29.876
//           s\.ffff: 29.8765
//          s\.fffff: 29.87654
//         s\.ffffff: 29.876543
//        s\.fffffff: 29.8765432      

Back to table

The "fff" Custom Format Specifier

The "fff" custom format specifier (with three "f" characters) outputs the milliseconds in a time interval. In a formatting operation, any remaining fractional digits are truncated. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the input string must contain exactly three fractional digits.

The following example uses the "fff" custom format specifier to display the milliseconds in a TimeSpan value. "fff" is used first as the only format specifier, and then combined with the "s" specifier in a custom format string.

Dim ts As New TimeSpan(1003498765432)
Dim fmt As String
outputBlock.Text += ts.ToString("c") + vbCrLf
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   If fmt.Length = 1 Then fmt = "%" + fmt
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", fmt, ts) + vbCrLf
Next 
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   outputBlock.Text += String.Format("{0,10}: {1:s\." + fmt + "}", "s\." + fmt, ts) + vbCrLf
Next
' The example displays the following output:
'            %f: 8
'            ff: 87
'           fff: 876
'          ffff: 8765
'         fffff: 87654
'        ffffff: 876543
'       fffffff: 8765432
'    
'           s\.f: 29.8
'          s\.ff: 29.87
'         s\.fff: 29.876
'        s\.ffff: 29.8765
'       s\.fffff: 29.87654
'      s\.ffffff: 29.876543
'     s\.fffffff: 29.8765432
TimeSpan ts = new TimeSpan(1003498765432);
string fmt;
outputBlock.Text += ts.ToString("c") + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   if (fmt.Length == 1) fmt = "%" + fmt;
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", 
                                     fmt, ts) + Environment.NewLine;
} 
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   outputBlock.Text += String.Format("{0,10}: {1:s\\." + fmt + "}", "s\\." + fmt, 
                                     ts) + Environment.NewLine;
}
// The example displays the following output:
//               %f: 8
//               ff: 87
//              fff: 876
//             ffff: 8765
//            fffff: 87654
//           ffffff: 876543
//          fffffff: 8765432
//       
//              s\.f: 29.8
//             s\.ff: 29.87
//            s\.fff: 29.876
//           s\.ffff: 29.8765
//          s\.fffff: 29.87654
//         s\.ffffff: 29.876543
//        s\.fffffff: 29.8765432      

Back to table

The "ffff" Custom Format Specifier

The "ffff" custom format specifier (with four "f" characters) outputs the ten-thousandths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the input string must contain exactly four fractional digits.

The following example uses the "ffff" custom format specifier to display the ten-thousandths of a second in a TimeSpan value. "ffff" is used first as the only format specifier, and then combined with the "s" specifier in a custom format string.

Dim ts As New TimeSpan(1003498765432)
Dim fmt As String
outputBlock.Text += ts.ToString("c") + vbCrLf
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   If fmt.Length = 1 Then fmt = "%" + fmt
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", fmt, ts) + vbCrLf
Next 
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   outputBlock.Text += String.Format("{0,10}: {1:s\." + fmt + "}", "s\." + fmt, ts) + vbCrLf
Next
' The example displays the following output:
'            %f: 8
'            ff: 87
'           fff: 876
'          ffff: 8765
'         fffff: 87654
'        ffffff: 876543
'       fffffff: 8765432
'    
'           s\.f: 29.8
'          s\.ff: 29.87
'         s\.fff: 29.876
'        s\.ffff: 29.8765
'       s\.fffff: 29.87654
'      s\.ffffff: 29.876543
'     s\.fffffff: 29.8765432
TimeSpan ts = new TimeSpan(1003498765432);
string fmt;
outputBlock.Text += ts.ToString("c") + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   if (fmt.Length == 1) fmt = "%" + fmt;
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", 
                                     fmt, ts) + Environment.NewLine;
} 
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   outputBlock.Text += String.Format("{0,10}: {1:s\\." + fmt + "}", "s\\." + fmt, 
                                     ts) + Environment.NewLine;
}
// The example displays the following output:
//               %f: 8
//               ff: 87
//              fff: 876
//             ffff: 8765
//            fffff: 87654
//           ffffff: 876543
//          fffffff: 8765432
//       
//              s\.f: 29.8
//             s\.ff: 29.87
//            s\.fff: 29.876
//           s\.ffff: 29.8765
//          s\.fffff: 29.87654
//         s\.ffffff: 29.876543
//        s\.fffffff: 29.8765432      

Back to table

The "fffff" Custom Format Specifier

The "fffff" custom format specifier (with five "f" characters) outputs the hundred-thousandths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the input string must contain exactly five fractional digits.

The following example uses the "fffff" custom format specifier to display the hundred-thousandths of a second in a TimeSpan value. "fffff" is used first as the only format specifier, and then combined with the "s" specifier in a custom format string.

Dim ts As New TimeSpan(1003498765432)
Dim fmt As String
outputBlock.Text += ts.ToString("c") + vbCrLf
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   If fmt.Length = 1 Then fmt = "%" + fmt
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", fmt, ts) + vbCrLf
Next 
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   outputBlock.Text += String.Format("{0,10}: {1:s\." + fmt + "}", "s\." + fmt, ts) + vbCrLf
Next
' The example displays the following output:
'            %f: 8
'            ff: 87
'           fff: 876
'          ffff: 8765
'         fffff: 87654
'        ffffff: 876543
'       fffffff: 8765432
'    
'           s\.f: 29.8
'          s\.ff: 29.87
'         s\.fff: 29.876
'        s\.ffff: 29.8765
'       s\.fffff: 29.87654
'      s\.ffffff: 29.876543
'     s\.fffffff: 29.8765432
TimeSpan ts = new TimeSpan(1003498765432);
string fmt;
outputBlock.Text += ts.ToString("c") + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   if (fmt.Length == 1) fmt = "%" + fmt;
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", 
                                     fmt, ts) + Environment.NewLine;
} 
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   outputBlock.Text += String.Format("{0,10}: {1:s\\." + fmt + "}", "s\\." + fmt, 
                                     ts) + Environment.NewLine;
}
// The example displays the following output:
//               %f: 8
//               ff: 87
//              fff: 876
//             ffff: 8765
//            fffff: 87654
//           ffffff: 876543
//          fffffff: 8765432
//       
//              s\.f: 29.8
//             s\.ff: 29.87
//            s\.fff: 29.876
//           s\.ffff: 29.8765
//          s\.fffff: 29.87654
//         s\.ffffff: 29.876543
//        s\.fffffff: 29.8765432      

Back to table

The "ffffff" Custom Format Specifier

The "ffffff" custom format specifier (with six "f" characters) outputs the millionths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the input string must contain exactly six fractional digits.

The following example uses the "ffffff" custom format specifier to display the millionths of a second in a TimeSpan value. It is used first as the only format specifier, and then combined with the "s" specifier in a custom format string.

Dim ts As New TimeSpan(1003498765432)
Dim fmt As String
outputBlock.Text += ts.ToString("c") + vbCrLf
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   If fmt.Length = 1 Then fmt = "%" + fmt
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", fmt, ts) + vbCrLf
Next 
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   outputBlock.Text += String.Format("{0,10}: {1:s\." + fmt + "}", "s\." + fmt, ts) + vbCrLf
Next
' The example displays the following output:
'            %f: 8
'            ff: 87
'           fff: 876
'          ffff: 8765
'         fffff: 87654
'        ffffff: 876543
'       fffffff: 8765432
'    
'           s\.f: 29.8
'          s\.ff: 29.87
'         s\.fff: 29.876
'        s\.ffff: 29.8765
'       s\.fffff: 29.87654
'      s\.ffffff: 29.876543
'     s\.fffffff: 29.8765432
TimeSpan ts = new TimeSpan(1003498765432);
string fmt;
outputBlock.Text += ts.ToString("c") + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   if (fmt.Length == 1) fmt = "%" + fmt;
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", 
                                     fmt, ts) + Environment.NewLine;
} 
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   outputBlock.Text += String.Format("{0,10}: {1:s\\." + fmt + "}", "s\\." + fmt, 
                                     ts) + Environment.NewLine;
}
// The example displays the following output:
//               %f: 8
//               ff: 87
//              fff: 876
//             ffff: 8765
//            fffff: 87654
//           ffffff: 876543
//          fffffff: 8765432
//       
//              s\.f: 29.8
//             s\.ff: 29.87
//            s\.fff: 29.876
//           s\.ffff: 29.8765
//          s\.fffff: 29.87654
//         s\.ffffff: 29.876543
//        s\.fffffff: 29.8765432      

Back to table

The "fffffff" Custom Format Specifier

The "fffffff" custom format specifier (with seven "f" characters) outputs the ten-millionths of a second (or the fractional number of ticks) in a time interval. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the input string must contain exactly seven fractional digits.

The following example uses the "fffffff" custom format specifier to display the fractional number of ticks in a TimeSpan value. It is used first as the only format specifier, and then combined with the "s" specifier in a custom format string.

Dim ts As New TimeSpan(1003498765432)
Dim fmt As String
outputBlock.Text += ts.ToString("c") + vbCrLf
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   If fmt.Length = 1 Then fmt = "%" + fmt
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", fmt, ts) + vbCrLf
Next 
outputBlock.Text += vbCrLf

For ctr = 1 To 7
   fmt = New String("f"c, ctr)
   outputBlock.Text += String.Format("{0,10}: {1:s\." + fmt + "}", "s\." + fmt, ts) + vbCrLf
Next
' The example displays the following output:
'            %f: 8
'            ff: 87
'           fff: 876
'          ffff: 8765
'         fffff: 87654
'        ffffff: 876543
'       fffffff: 8765432
'    
'           s\.f: 29.8
'          s\.ff: 29.87
'         s\.fff: 29.876
'        s\.ffff: 29.8765
'       s\.fffff: 29.87654
'      s\.ffffff: 29.876543
'     s\.fffffff: 29.8765432
TimeSpan ts = new TimeSpan(1003498765432);
string fmt;
outputBlock.Text += ts.ToString("c") + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   if (fmt.Length == 1) fmt = "%" + fmt;
   outputBlock.Text += String.Format("{0,10}: {1:" + fmt + "}", 
                                     fmt, ts) + Environment.NewLine;
} 
outputBlock.Text += Environment.NewLine;

for (int ctr = 1; ctr <= 7; ctr++) {
   fmt = new String('f', ctr);
   outputBlock.Text += String.Format("{0,10}: {1:s\\." + fmt + "}", "s\\." + fmt, 
                                     ts) + Environment.NewLine;
}
// The example displays the following output:
//               %f: 8
//               ff: 87
//              fff: 876
//             ffff: 8765
//            fffff: 87654
//           ffffff: 876543
//          fffffff: 8765432
//       
//              s\.f: 29.8
//             s\.ff: 29.87
//            s\.fff: 29.876
//           s\.ffff: 29.8765
//          s\.fffff: 29.87654
//         s\.ffffff: 29.876543
//        s\.fffffff: 29.8765432      

Back to table

The "F" Custom Format Specifier

The "F" custom format specifier outputs the tenths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. If the value of the time interval's tenths of a second is zero, it is not included in the result string. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the presence of the tenths of a second digit is optional.

If the "F" custom format specifier is used alone, specify "%F" so that it is not misinterpreted as a standard format string.

The following example uses the "F" custom format specifier to display the tenths of a second in a TimeSpan value. It also uses this custom format specifier in a parsing operation.

outputBlock.Text += "Formatting:" + vbCrLf
Dim ts1 As TimeSpan = TimeSpan.Parse("0:0:3.669")
outputBlock.Text += String.Format("{0} ('%F') --> {0:%F}", ts1) + vbCrLf

Dim ts2 As TimeSpan = TimeSpan.Parse("0:0:3.091")
outputBlock.Text += String.Format("{0} ('ss\.F') --> {0:ss\.F}", ts2) + vbCrLf
outputBlock.Text +=  vbCrLf

outputBlock.Text += "Parsing:" + vbCrLf
Dim inputs() As String = { "0:0:03.", "0:0:03.1", "0:0:03.12" }
Dim fmt As String = "h\:m\:ss\.F"
Dim ts3 As TimeSpan

For Each input As String In inputs
   If TimeSpan.TryParseExact(input, fmt, Nothing, ts3)
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", input, fmt, ts3) + vbCrLf
   Else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + vbCrLf
   End If  
Next
' The example displays the following output:
'       Formatting:
'       00:00:03.6690000 ('%F') --> 6
'       00:00:03.0910000 ('ss\.F') --> 03.
'       
'       Parsing:
'       0:0:03. ('h\:m\:ss\.F') --> 00:00:03
'       0:0:03.1 ('h\:m\:ss\.F') --> 00:00:03.1000000
'       Cannot parse 0:0:03.12 with 'h\:m\:ss\.F'.      
outputBlock.Text += "Formatting:" + Environment.NewLine;
TimeSpan ts1 = TimeSpan.Parse("0:0:3.669");
outputBlock.Text += String.Format("{0} ('%F') --> {0:%F}", 
                                  ts1) + Environment.NewLine;

TimeSpan ts2 = TimeSpan.Parse("0:0:3.091");
outputBlock.Text += String.Format("{0} ('ss\\.F') --> {0:ss\\.F}", 
                                  ts2) + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

outputBlock.Text += "Parsing:" + Environment.NewLine;
string[] inputs = { "0:0:03.", "0:0:03.1", "0:0:03.12" };
string fmt = @"h\:m\:ss\.F";
TimeSpan ts3;

foreach (string input in inputs) {
   if (TimeSpan.TryParseExact(input, fmt, null, out ts3))
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + Environment.NewLine;
   else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + Environment.NewLine;
}                        
// The example displays the following output:
//       Formatting:
//       00:00:03.6690000 ('%F') --> 6
//       00:00:03.0910000 ('ss\.F') --> 03.
//       
//       Parsing:
//       0:0:03. ('h\:m\:ss\.F') --> 00:00:03
//       0:0:03.1 ('h\:m\:ss\.F') --> 00:00:03.1000000
//       Cannot parse 0:0:03.12 with 'h\:m\:ss\.F'.      

Back to table

The "FF" Custom Format Specifier

The "FF" custom format specifier outputs the hundredths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. If there are any trailing fractional zeros, they are not included in the result string. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the presence of the tenths and hundredths of a second digit is optional.

The following example uses the "FF" custom format specifier to display the hundredths of a second in a TimeSpan value. It also uses this custom format specifier in a parsing operation.

outputBlock.Text += "Formatting:" + vbCrLf
Dim ts1 As TimeSpan = TimeSpan.Parse("0:0:3.697")
outputBlock.Text += String.Format("{0} ('FF') --> {0:FF}", ts1) + vbCrLf

Dim ts2 As TimeSpan = TimeSpan.Parse("0:0:3.809")
outputBlock.Text += String.Format("{0} ('ss\.FF') --> {0:ss\.FF}", ts2) + vbCrLf
outputBlock.Text +=  vbCrLf

outputBlock.Text += "Parsing:" + vbCrLf
Dim inputs() As String = { "0:0:03.", "0:0:03.1", "0:0:03.127" }
Dim fmt As String = "h\:m\:ss\.FF"
Dim ts3 As TimeSpan

For Each input As String In inputs
   If TimeSpan.TryParseExact(input, fmt, Nothing, ts3)
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", input, fmt, ts3) + vbCrLf
   Else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + vbCrLf
   End If  
Next
' The example displays the following output:
'       Formatting:
'       00:00:03.6970000 ('FF') --> 69
'       00:00:03.8090000 ('ss\.FF') --> 03.8
'       
'       Parsing:
'       0:0:03. ('h\:m\:ss\.FF') --> 00:00:03
'       0:0:03.1 ('h\:m\:ss\.FF') --> 00:00:03.1000000
'       Cannot parse 0:0:03.127 with 'h\:m\:ss\.FF'.
outputBlock.Text += "Formatting:" + Environment.NewLine;
TimeSpan ts1 = TimeSpan.Parse("0:0:3.697");
outputBlock.Text += String.Format("{0} ('FF') --> {0:FF}", 
                                  ts1) + Environment.NewLine;

TimeSpan ts2 = TimeSpan.Parse("0:0:3.809");
outputBlock.Text += String.Format("{0} ('ss\\.FF') --> {0:ss\\.FF}", 
                                  ts2) + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

outputBlock.Text += "Parsing:" + Environment.NewLine;
string[] inputs = { "0:0:03.", "0:0:03.1", "0:0:03.127" };
string fmt = @"h\:m\:ss\.FF";
TimeSpan ts3;

foreach (string input in inputs) {
   if (TimeSpan.TryParseExact(input, fmt, null, out ts3))
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + Environment.NewLine;
   else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + Environment.NewLine;
}
// The example displays the following output:
//       Formatting:
//       00:00:03.6970000 ('FF') --> 69
//       00:00:03.8090000 ('ss\.FF') --> 03.8
//       
//       Parsing:
//       0:0:03. ('h\:m\:ss\.FF') --> 00:00:03
//       0:0:03.1 ('h\:m\:ss\.FF') --> 00:00:03.1000000
//       Cannot parse 0:0:03.127 with 'h\:m\:ss\.FF'.      

Back to table

The "FFF" Custom Format Specifier

The "FFF" custom format specifier (with three "F" characters) outputs the milliseconds in a time interval. In a formatting operation, any remaining fractional digits are truncated. If there are any trailing fractional zeros, they are not included in the result string. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the presence of the tenths, hundredths, and thousandths of a second digit is optional.

The following example uses the "FFF" custom format specifier to display the thousandths of a second in a TimeSpan value. It also uses this custom format specifier in a parsing operation.

outputBlock.Text += "Formatting:" + vbCrLf
Dim ts1 As TimeSpan = TimeSpan.Parse("0:0:3.6974")
outputBlock.Text += String.Format("{0} ('FFF') --> {0:FFF}", ts1) + vbCrLf

Dim ts2 As TimeSpan = TimeSpan.Parse("0:0:3.8009")
outputBlock.Text += String.Format("{0} ('ss\.FFF') --> {0:ss\.FFF}", ts2) + vbCrLf
outputBlock.Text +=  vbCrLf

outputBlock.Text += "Parsing:" + vbCrLf
Dim inputs() As String = { "0:0:03.", "0:0:03.12", "0:0:03.1279" }
Dim fmt As String = "h\:m\:ss\.FFF"
Dim ts3 As TimeSpan

For Each input As String In inputs
   If TimeSpan.TryParseExact(input, fmt, Nothing, ts3)
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", input, fmt, ts3) + vbCrLf
   Else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + vbCrLf
   End If  
Next
' The example displays the following output:
'       Formatting:
'       00:00:03.6974000 ('FFF') --> 697
'       00:00:03.8009000 ('ss\.FFF') --> 03.8
'       
'       Parsing:
'       0:0:03. ('h\:m\:ss\.FFF') --> 00:00:03
'       0:0:03.12 ('h\:m\:ss\.FFF') --> 00:00:03.1200000
'       Cannot parse 0:0:03.1279 with 'h\:m\:ss\.FFF'.
outputBlock.Text += "Formatting:" + Environment.NewLine;
TimeSpan ts1 = TimeSpan.Parse("0:0:3.6974");
outputBlock.Text += String.Format("{0} ('FFF') --> {0:FFF}", 
                                  ts1) + Environment.NewLine;

TimeSpan ts2 = TimeSpan.Parse("0:0:3.8009");
outputBlock.Text += String.Format("{0} ('ss\\.FFF') --> {0:ss\\.FFF}", 
                                  ts2) + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

outputBlock.Text += "Parsing:" + Environment.NewLine;
string[] inputs = { "0:0:03.", "0:0:03.12", "0:0:03.1279" };
string fmt = @"h\:m\:ss\.FFF";
TimeSpan ts3;

foreach (string input in inputs) {
   if (TimeSpan.TryParseExact(input, fmt, null, out ts3))
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + Environment.NewLine;
   else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + Environment.NewLine;
}
// The example displays the following output:
//       Formatting:
//       00:00:03.6974000 ('FFF') --> 697
//       00:00:03.8009000 ('ss\.FFF') --> 03.8
//       
//       Parsing:
//       0:0:03. ('h\:m\:ss\.FFF') --> 00:00:03
//       0:0:03.12 ('h\:m\:ss\.FFF') --> 00:00:03.1200000
//       Cannot parse 0:0:03.1279 with 'h\:m\:ss\.FFF'.      

Back to table

The "FFFF" Custom Format Specifier

The "FFFF" custom format specifier (with four "F" characters) outputs the ten-thousandths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. If there are any trailing fractional zeros, they are not included in the result string. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the presence of the tenths, hundredths, thousandths, and ten-thousandths of a second digit is optional.

The following example uses the "FFFF" custom format specifier to display the ten-thousandths of a second in a TimeSpan value. It also uses the "FFFF" custom format specifier in a parsing operation.

outputBlock.Text += "Formatting:" + vbCrLf
Dim ts1 As TimeSpan = TimeSpan.Parse("0:0:3.69749")
outputBlock.Text += String.Format("{0} ('FFFF') --> {0:FFFF}", ts1) + vbCrLf

Dim ts2 As TimeSpan = TimeSpan.Parse("0:0:3.80009")
outputBlock.Text += String.Format("{0} ('ss\.FFFF') --> {0:ss\.FFFF}", ts2) + vbCrLf
outputBlock.Text += vbCrLf

outputBlock.Text += "Parsing:" + vbCrLf
Dim inputs() As String = { "0:0:03.", "0:0:03.12", "0:0:03.12795" }
Dim fmt As String = "h\:m\:ss\.FFFF"
Dim ts3 As TimeSpan

For Each input As String In inputs
   If TimeSpan.TryParseExact(input, fmt, Nothing, ts3)
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + vbCrLf
   Else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + vbCrLf
   End If  
Next
' The example displays the following output:
'       Formatting:
'       00:00:03.6974900 ('FFFF') --> 6974
'       00:00:03.8000900 ('ss\.FFFF') --> 03.8
'       
'       Parsing:
'       0:0:03. ('h\:m\:ss\.FFFF') --> 00:00:03
'       0:0:03.12 ('h\:m\:ss\.FFFF') --> 00:00:03.1200000
'       Cannot parse 0:0:03.12795 with 'h\:m\:ss\.FFFF'.
outputBlock.Text += "Formatting:" + Environment.NewLine;
TimeSpan ts1 = TimeSpan.Parse("0:0:3.69749");
outputBlock.Text += String.Format("{0} ('FFFF') --> {0:FFFF}", 
                                  ts1) + Environment.NewLine;

TimeSpan ts2 = TimeSpan.Parse("0:0:3.80009");
outputBlock.Text += String.Format("{0} ('ss\\.FFFF') --> {0:ss\\.FFFF}", 
                                  ts2) + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

outputBlock.Text += "Parsing:" + Environment.NewLine;
string[] inputs = { "0:0:03.", "0:0:03.12", "0:0:03.12795" };
string fmt = @"h\:m\:ss\.FFFF";
TimeSpan ts3;

foreach (string input in inputs) {
   if (TimeSpan.TryParseExact(input, fmt, null, out ts3))
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + Environment.NewLine;
   else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + Environment.NewLine;
}
// The example displays the following output:
//       Formatting:
//       00:00:03.6974900 ('FFFF') --> 6974
//       00:00:03.8000900 ('ss\.FFFF') --> 03.8
//       
//       Parsing:
//       0:0:03. ('h\:m\:ss\.FFFF') --> 00:00:03
//       0:0:03.12 ('h\:m\:ss\.FFFF') --> 00:00:03.1200000
//       Cannot parse 0:0:03.12795 with 'h\:m\:ss\.FFFF'.

Back to table

The "FFFFF" Custom Format Specifier

The "FFFFF" custom format specifier (with five "F" characters) outputs the hundred-thousandths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. If there are any trailing fractional zeros, they are not included in the result string. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the presence of the tenths, hundredths, thousandths, ten-thousandths, and hundred-thousandths of a second digit is optional.

The following example uses the "FFFFF" custom format specifier to display the hundred-thousandths of a second in a TimeSpan value. It also uses the "FFFFF" custom format specifier in a parsing operation.

outputBlock.Text += "Formatting:" + vbCrLf 
Dim ts1 As TimeSpan = TimeSpan.Parse("0:0:3.697497")
outputBlock.Text += String.Format("{0} ('FFFFF') --> {0:FFFFF}", ts1) + vbCrLf

Dim ts2 As TimeSpan = TimeSpan.Parse("0:0:3.800009")
outputBlock.Text += String.Format("{0} ('ss\.FFFFF') --> {0:ss\.FFFFF}", 
                                  ts2) + vbCrLf
outputBlock.Text += vbCrLf

outputBlock.Text += "Parsing:" + vbCrLf
Dim inputs() As String = { "0:0:03.", "0:0:03.12", "0:0:03.127956" }
Dim fmt As String = "h\:m\:ss\.FFFFF"
Dim ts3 As TimeSpan

For Each input As String In inputs
   If TimeSpan.TryParseExact(input, fmt, Nothing, ts3)
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + vbCrLf
   Else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt)  + vbCrLf
   End If  
Next
' The example displays the following output:
'       Formatting:
'       00:00:03.6974970 ('FFFFF') --> 69749
'       00:00:03.8000090 ('ss\.FFFFF') --> 03.8
'       
'       Parsing:
'       0:0:03. ('h\:m\:ss\.FFFF') --> 00:00:03
'       0:0:03.12 ('h\:m\:ss\.FFFF') --> 00:00:03.1200000
'       Cannot parse 0:0:03.127956 with 'h\:m\:ss\.FFFF'.
outputBlock.Text += "Formatting:" + Environment.NewLine;
TimeSpan ts1 = TimeSpan.Parse("0:0:3.697497");
outputBlock.Text += String.Format("{0} ('FFFFF') --> {0:FFFFF}", 
                                  ts1) + Environment.NewLine;

TimeSpan ts2 = TimeSpan.Parse("0:0:3.800009");
outputBlock.Text += String.Format("{0} ('ss\\.FFFFF') --> {0:ss\\.FFFFF}", 
                                  ts2) + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

outputBlock.Text += "Parsing:" + Environment.NewLine;
string[] inputs = { "0:0:03.", "0:0:03.12", "0:0:03.127956" };
string fmt = @"h\:m\:ss\.FFFFF";
TimeSpan ts3;

foreach (string input in inputs) {
   if (TimeSpan.TryParseExact(input, fmt, null, out ts3))
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + Environment.NewLine;
   else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + Environment.NewLine;
}                       
// The example displays the following output:
//       Formatting:
//       00:00:03.6974970 ('FFFFF') --> 69749
//       00:00:03.8000090 ('ss\.FFFFF') --> 03.8
//       
//       Parsing:
//       0:0:03. ('h\:m\:ss\.FFFF') --> 00:00:03
//       0:0:03.12 ('h\:m\:ss\.FFFF') --> 00:00:03.1200000
//       Cannot parse 0:0:03.127956 with 'h\:m\:ss\.FFFF'.      

Back to table

The "FFFFFF" Custom Format Specifier

The "FFFFFF" custom format specifier (with six "F" characters) outputs the millionths of a second in a time interval. In a formatting operation, any remaining fractional digits are truncated. If there are any trailing fractional zeros, they are not included in the result string. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the presence of the tenths, hundredths, thousandths, ten-thousandths, hundred-thousandths, and millionths of a second digit is optional.

The following example uses the "FFFFFF" custom format specifier to display the millionths of a second in a TimeSpan value. It also uses this custom format specifier in a parsing operation.

outputBlock.Text += "Formatting:" + vbCrLf
Dim ts1 As TimeSpan = TimeSpan.Parse("0:0:3.6974974")
outputBlock.Text += String.Format("{0} ('FFFFFF') --> {0:FFFFFF}", 
                                  ts1) + vbCrLf

Dim ts2 As TimeSpan = TimeSpan.Parse("0:0:3.8000009")
outputBlock.Text += String.Format("{0} ('ss\.FFFFFF') --> {0:ss\.FFFFFF}", 
                                  ts2) + vbCrLf
outputBlock.Text += vbCrLf

outputBlock.Text += "Parsing:" + vbCrLf
Dim inputs() As String = { "0:0:03.", "0:0:03.12", "0:0:03.1279569" }
Dim fmt As String = "h\:m\:ss\.FFFFFF"
Dim ts3 As TimeSpan

For Each input As String In inputs
   If TimeSpan.TryParseExact(input, fmt, Nothing, ts3)
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + vbCrLf
   Else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + vbCrLf
   End If  
Next
' The example displays the following output:
'       Formatting:
'       00:00:03.6974974 ('FFFFFF') --> 697497
'       00:00:03.8000009 ('ss\.FFFFFF') --> 03.8
'       
'       Parsing:
'       0:0:03. ('h\:m\:ss\.FFFFFF') --> 00:00:03
'       0:0:03.12 ('h\:m\:ss\.FFFFFF') --> 00:00:03.1200000
'       Cannot parse 0:0:03.1279569 with 'h\:m\:ss\.FFFFFF'.
outputBlock.Text += "Formatting:" + Environment.NewLine;
TimeSpan ts1 = TimeSpan.Parse("0:0:3.6974974");
outputBlock.Text += String.Format("{0} ('FFFFFF') --> {0:FFFFFF}", 
                                  ts1) + Environment.NewLine;

TimeSpan ts2 = TimeSpan.Parse("0:0:3.8000009");
outputBlock.Text += String.Format("{0} ('ss\\.FFFFFF') --> {0:ss\\.FFFFFF}", 
                                  ts2) + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

outputBlock.Text += "Parsing:" + Environment.NewLine;
string[] inputs = { "0:0:03.", "0:0:03.12", "0:0:03.1279569" };
string fmt = @"h\:m\:ss\.FFFFFF";
TimeSpan ts3;

foreach (string input in inputs) {
   if (TimeSpan.TryParseExact(input, fmt, null, out ts3))
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + Environment.NewLine;
   else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + Environment.NewLine;
}                       
// The example displays the following output:
//       Formatting:
//       00:00:03.6974974 ('FFFFFF') --> 697497
//       00:00:03.8000009 ('ss\.FFFFFF') --> 03.8
//       
//       Parsing:
//       0:0:03. ('h\:m\:ss\.FFFFFF') --> 00:00:03
//       0:0:03.12 ('h\:m\:ss\.FFFFFF') --> 00:00:03.1200000
//       Cannot parse 0:0:03.1279569 with 'h\:m\:ss\.FFFFFF'.      

Back to table

The "FFFFFFF" Custom Format Specifier

The "FFFFFFF" custom format specifier (with seven "F" characters) outputs the ten-millionths of a second (or the fractional number of ticks) in a time interval. If there are any trailing fractional zeros, they are not included in the result string. In a parsing operation that calls the TimeSpan.ParseExact or TimeSpan.TryParseExact method, the presence of the seven fractional digits in the input string is optional.

The following example uses the "FFFFFFF" custom format specifier to display the fractional parts of a second in a TimeSpan value. It also uses this custom format specifier in a parsing operation.

outputBlock.Text += "Formatting:" + vbCrLf
Dim ts1 As TimeSpan = TimeSpan.Parse("0:0:3.6974974")
outputBlock.Text += String.Format("{0} ('FFFFFFF') --> {0:FFFFFFF}", ts1) + vbCrLf

Dim ts2 As TimeSpan = TimeSpan.Parse("0:0:3.9500000")
outputBlock.Text += String.Format("{0} ('ss\.FFFFFFF') --> {0:ss\.FFFFFFF}", 
                                  ts2) + vbCrLf
outputBlock.Text += vbCrLf

outputBlock.Text += "Parsing:" + vbCrLf
Dim inputs() As String = { "0:0:03.", "0:0:03.12", "0:0:03.1279569" }
Dim fmt As String = "h\:m\:ss\.FFFFFFF"
Dim ts3 As TimeSpan

For Each input As String In inputs
   If TimeSpan.TryParseExact(input, fmt, Nothing, ts3)
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + vbCrLf
   Else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + vbCrLf
   End If  
Next
' The example displays the following output:
'    Formatting:
'    00:00:03.6974974 ('FFFFFFF') --> 6974974
'    00:00:03.9500000 ('ss\.FFFFFFF') --> 03.95
'    
'    Parsing:
'    0:0:03. ('h\:m\:ss\.FFFFFFF') --> 00:00:03
'    0:0:03.12 ('h\:m\:ss\.FFFFFFF') --> 00:00:03.1200000
'    0:0:03.1279569 ('h\:m\:ss\.FFFFFFF') --> 00:00:03.1279569     
outputBlock.Text += "Formatting:" + Environment.NewLine;
TimeSpan ts1 = TimeSpan.Parse("0:0:3.6974974");
outputBlock.Text += String.Format("{0} ('FFFFFFF') --> {0:FFFFFFF}", 
                                  ts1) + Environment.NewLine;

TimeSpan ts2 = TimeSpan.Parse("0:0:3.9500000");
outputBlock.Text += String.Format("{0} ('ss\\.FFFFFFF') --> {0:ss\\.FFFFFFF}", 
                                  ts2) + Environment.NewLine;
outputBlock.Text += Environment.NewLine;

outputBlock.Text += "Parsing:";
string[] inputs = { "0:0:03.", "0:0:03.12", "0:0:03.1279569" };
string fmt = @"h\:m\:ss\.FFFFFFF";
TimeSpan ts3;

foreach (string input in inputs) {
   if (TimeSpan.TryParseExact(input, fmt, null, out ts3))
      outputBlock.Text += String.Format("{0} ('{1}') --> {2}", 
                                        input, fmt, ts3) + Environment.NewLine;
   else
      outputBlock.Text += String.Format("Cannot parse {0} with '{1}'.", 
                                        input, fmt) + Environment.NewLine;
}
// The example displays the following output:
//    Formatting:
//    00:00:03.6974974 ('FFFFFFF') --> 6974974
//    00:00:03.9500000 ('ss\.FFFFFFF') --> 03.95
//    
//    Parsing:
//    0:0:03. ('h\:m\:ss\.FFFFFFF') --> 00:00:03
//    0:0:03.12 ('h\:m\:ss\.FFFFFFF') --> 00:00:03.1200000
//    0:0:03.1279569 ('h\:m\:ss\.FFFFFFF') --> 00:00:03.1279569      

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Other Characters

Any other unescaped character in a format string, including a white-space character, is interpreted as a custom format specifier. In most cases, the presence of any other unescaped character results in a FormatException.

There are two ways to include a literal character in a format string:

  • Enclose it in single quotation marks (the literal string delimiter).

  • Precede it with a backslash ("\"), which is interpreted as an escape character. This means that, in C#, the format string must either be @-quoted, or the literal character must be preceded by an additional backslash.

The .NET Framework does not define a grammar for separators in time intervals. This means that the separators between days and hours, hours and minutes, minutes and seconds, and seconds and fractions of a second must all be treated as character literals in a format string.

The following example uses both the escape character and the single quote to define a custom format string that includes the word "minutes" in the output string.

Dim interval As New TimeSpan(0, 32, 45)
' Escape literal characters in a format string.
Dim fmt As String = "mm\:ss\ \m\i\n\u\t\e\s"
outputBlock.Text += interval.ToString(fmt) + vbCrLf
' Delimit literal characters in a format string with the ' symbol.
fmt = "mm':'ss' minutes'"
outputBlock.Text += interval.ToString(fmt) + vbCrLf
' The example displays the following output: 
'       32:45 minutes      
'       32:45 minutes      
TimeSpan interval = new TimeSpan(0, 32, 45);
// Escape literal characters in a format string.
string fmt = @"mm\:ss\ \m\i\n\u\t\e\s";
outputBlock.Text += interval.ToString(fmt) + Environment.NewLine;
// Delimit literal characters in a format string with the ' symbol.
fmt = "mm':'ss' minutes'";      
outputBlock.Text += interval.ToString(fmt) + Environment.NewLine;
// The example displays the following output: 
//       32:45 minutes      
//       32:45 minutes      

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