Article
11/18/2011

CompareInfo.IndexOf Method (String, String, Int32, Int32, CompareOptions)

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Searches for the specified substring and returns the zero-based index of the first occurrence within the section of the source string that starts at the specified index and contains the specified number of elements using the specified CompareOptions value.

Namespace: System.Globalization
Assembly: mscorlib (in mscorlib.dll)

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Overridable Function IndexOf ( _
    source As String, _
    value As String, _
    startIndex As Integer, _
    count As Integer, _
    options As CompareOptions _
) As Integer

[SecuritySafeCriticalAttribute]
public virtual int IndexOf(
    string source,
    string value,
    int startIndex,
    int count,
    CompareOptions options
)

Parameters

source
Type: System.String
The string to search.

value
Type: System.String
The string to locate within source.

startIndex
Type: System.Int32
The zero-based starting index of the search.

count
Type: System.Int32
The number of elements in the section to search.

options
Type: System.Globalization.CompareOptions
The CompareOptions value that defines how source and value should be compared. options is either the value Ordinal used by itself, or the bitwise combination of one or more of the following values: IgnoreCase, IgnoreSymbols, IgnoreNonSpace, IgnoreWidth, and IgnoreKanaType.

Return Value

Type: System.Int32
The zero-based index of the first occurrence of value within the section of source that starts at startIndex and contains the number of elements specified by count, using the specified CompareOptions value, if found; otherwise, -1.

Exceptions

Exception	Condition
ArgumentNullException	source is nulla null reference (Nothing in Visual Basic). -or- value is nulla null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException	startIndex is outside the range of valid indexes for source. -or- count is less than zero. -or- startIndex and count do not specify a valid section in source.
ArgumentException	options contains an invalid CompareOptions value.

ArgumentNullException

source is nulla null reference (Nothing in Visual Basic).

-or-

value is nulla null reference (Nothing in Visual Basic).

ArgumentOutOfRangeException

startIndex is outside the range of valid indexes for source.

-or-

count is less than zero.

-or-

startIndex and count do not specify a valid section in source.

ArgumentException

options contains an invalid CompareOptions value.

Remarks

The source string is searched forward starting at startIndex and ending at startIndex + count - 1.

The CompareOptions.StringSort value is not valid for this method.

If options does not include the Ordinal value, this overload performs a culture-sensitive search. A Unicode value representing a precomposed character, such as the ligature "Æ" (U+00C6), might be considered equivalent to any occurrence of the character's components in the correct sequence, such as "AE" (U+0041, U+0045), depending on the culture. If options includes the Ordinal value, this overload performs an ordinal (culture-insensitive) search, where the Unicode values are compared.

Examples

The following example determines the indexes of the first and last occurrences of a character or a substring within a portion of a string.

Imports System.Globalization

Public Class Example

   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

      ' Creates CompareInfo for the InvariantCulture.
      Dim myComp As CompareInfo = CultureInfo.InvariantCulture.CompareInfo

      ' iS is the starting index of the substring.
      Dim [iS] As Integer = 8
      ' iL is the length of the substring.
      Dim iL As Integer = 18
      ' myT1 and myT2 are the strings used for padding.
      Dim myT1 As New [String]("-"c, [iS])
      Dim myT2 As [String]

      ' Searches for the ligature Æ.
      Dim myStr As [String] = "Is AE or ae the same as Æ or æ?"
      myT2 = New [String]("-"c, myStr.Length - [iS] - iL)
      outputBlock.Text &= vbCrLf
      outputBlock.Text += String.Format("Original      : {0}", myStr) & vbCrLf
      outputBlock.Text += String.Format("No options    : {0}{1}{2}", myT1, myStr.Substring([iS], iL), myT2) & vbCrLf
      PrintMarker(outputBlock, "           AE : ", myComp.IndexOf(myStr, "AE", [iS], iL), myComp.LastIndexOf(myStr, "AE", [iS] + iL - 1, iL))
      PrintMarker(outputBlock, "           ae : ", myComp.IndexOf(myStr, "ae", [iS], iL), myComp.LastIndexOf(myStr, "ae", [iS] + iL - 1, iL))
      PrintMarker(outputBlock, "            Æ : ", myComp.IndexOf(myStr, "Æ"c, [iS], iL), myComp.LastIndexOf(myStr, "Æ"c, [iS] + iL - 1, iL))
      PrintMarker(outputBlock, "            æ : ", myComp.IndexOf(myStr, "æ"c, [iS], iL), myComp.LastIndexOf(myStr, "æ"c, [iS] + iL - 1, iL))
      outputBlock.Text += String.Format("Ordinal       : {0}{1}{2}", myT1, myStr.Substring([iS], iL), myT2) & vbCrLf
      PrintMarker(outputBlock, "           AE : ", myComp.IndexOf(myStr, "AE", [iS], iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "AE", [iS] + iL - 1, iL, CompareOptions.Ordinal))
      PrintMarker(outputBlock, "           ae : ", myComp.IndexOf(myStr, "ae", [iS], iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "ae", [iS] + iL - 1, iL, CompareOptions.Ordinal))
      PrintMarker(outputBlock, "            Æ : ", myComp.IndexOf(myStr, "Æ"c, [iS], iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "Æ"c, [iS] + iL - 1, iL, CompareOptions.Ordinal))
      PrintMarker(outputBlock, "            æ : ", myComp.IndexOf(myStr, "æ"c, [iS], iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "æ"c, [iS] + iL - 1, iL, CompareOptions.Ordinal))
      outputBlock.Text += String.Format("IgnoreCase    : {0}{1}{2}", myT1, myStr.Substring([iS], iL), myT2) & vbCrLf
      PrintMarker(outputBlock, "           AE : ", myComp.IndexOf(myStr, "AE", [iS], iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "AE", [iS] + iL - 1, iL, CompareOptions.IgnoreCase))
      PrintMarker(outputBlock, "           ae : ", myComp.IndexOf(myStr, "ae", [iS], iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "ae", [iS] + iL - 1, iL, CompareOptions.IgnoreCase))
      PrintMarker(outputBlock, "            Æ : ", myComp.IndexOf(myStr, "Æ"c, [iS], iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "Æ"c, [iS] + iL - 1, iL, CompareOptions.IgnoreCase))
      PrintMarker(outputBlock, "            æ : ", myComp.IndexOf(myStr, "æ"c, [iS], iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "æ"c, [iS] + iL - 1, iL, CompareOptions.IgnoreCase))

      ' Searches for the combining character sequence Latin capital letter U with diaeresis or Latin small letter u with diaeresis.
      myStr = "Is " & ChrW(&H55) & ChrW(&H308) & " or " & ChrW(&H75) & ChrW(&H308) & " the same as " & ChrW(&HDC) & " or " & ChrW(&HFC) & "?"
      myT2 = New [String]("-"c, myStr.Length - [iS] - iL)
      outputBlock.Text &= vbCrLf
      outputBlock.Text += String.Format("Original      : {0}", myStr) & vbCrLf
      outputBlock.Text += String.Format("No options    : {0}{1}{2}", myT1, myStr.Substring([iS], iL), myT2) & vbCrLf
      PrintMarker(outputBlock, "           U" & ChrW(&H308) & " : ", myComp.IndexOf(myStr, "U" & ChrW(&H308), [iS], iL), myComp.LastIndexOf(myStr, "U" & ChrW(&H308), [iS] + iL - 1, iL))
      PrintMarker(outputBlock, "           u" & ChrW(&H308) & " : ", myComp.IndexOf(myStr, "u" & ChrW(&H308), [iS], iL), myComp.LastIndexOf(myStr, "u" & ChrW(&H308), [iS] + iL - 1, iL))
      PrintMarker(outputBlock, "            Ü : ", myComp.IndexOf(myStr, "Ü"c, [iS], iL), myComp.LastIndexOf(myStr, "Ü"c, [iS] + iL - 1, iL))
      PrintMarker(outputBlock, "            ü : ", myComp.IndexOf(myStr, "ü"c, [iS], iL), myComp.LastIndexOf(myStr, "ü"c, [iS] + iL - 1, iL))
      outputBlock.Text += String.Format("Ordinal       : {0}{1}{2}", myT1, myStr.Substring([iS], iL), myT2) & vbCrLf
      PrintMarker(outputBlock, "           U" & ChrW(&H308) & " : ", myComp.IndexOf(myStr, "U" & ChrW(&H308), [iS], iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "U" & ChrW(&H308), [iS] + iL - 1, iL, CompareOptions.Ordinal))
      PrintMarker(outputBlock, "           u" & ChrW(&H308) & " : ", myComp.IndexOf(myStr, "u" & ChrW(&H308), [iS], iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "u" & ChrW(&H308), [iS] + iL - 1, iL, CompareOptions.Ordinal))
      PrintMarker(outputBlock, "            Ü : ", myComp.IndexOf(myStr, "Ü"c, [iS], iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "Ü"c, [iS] + iL - 1, iL, CompareOptions.Ordinal))
      PrintMarker(outputBlock, "            ü : ", myComp.IndexOf(myStr, "ü"c, [iS], iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "ü"c, [iS] + iL - 1, iL, CompareOptions.Ordinal))
      outputBlock.Text += String.Format("IgnoreCase    : {0}{1}{2}", myT1, myStr.Substring([iS], iL), myT2) & vbCrLf
      PrintMarker(outputBlock, "           U" & ChrW(&H308) & " : ", myComp.IndexOf(myStr, "U" & ChrW(&H308), [iS], iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "U" & ChrW(&H308), [iS] + iL - 1, iL, CompareOptions.IgnoreCase))
      PrintMarker(outputBlock, "           u" & ChrW(&H308) & " : ", myComp.IndexOf(myStr, "u" & ChrW(&H308), [iS], iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "u" & ChrW(&H308), [iS] + iL - 1, iL, CompareOptions.IgnoreCase))
      PrintMarker(outputBlock, "            Ü : ", myComp.IndexOf(myStr, "Ü"c, [iS], iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "Ü"c, [iS] + iL - 1, iL, CompareOptions.IgnoreCase))
      PrintMarker(outputBlock, "            ü : ", myComp.IndexOf(myStr, "ü"c, [iS], iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "ü"c, [iS] + iL - 1, iL, CompareOptions.IgnoreCase))

   End Sub 'Main

   Public Shared Sub PrintMarker(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal Prefix As [String], ByVal First As Integer, ByVal Last As Integer)

      ' Determines the size of the array to create.
      Dim mySize As Integer
      If Last > First Then
         mySize = Last
      Else
         mySize = First
      End If

      If mySize > -1 Then

         ' Creates an array of Char to hold the markers.
         Dim myCharArr(mySize + 1) As [Char]

         ' Inserts the appropriate markers.
         If First > -1 Then
            myCharArr(First) = "f"c
         End If
         If Last > -1 Then
            myCharArr(Last) = "l"c
         End If
         If First = Last Then
            myCharArr(First) = "b"c
         End If

         ' Displays the array of Char as a String.
         outputBlock.Text += String.Format("{0}{1}", Prefix, New [String](myCharArr)) & vbCrLf

      Else
         outputBlock.Text &= Prefix & vbCrLf

      End If

   End Sub 'PrintMarker

End Class 'SamplesCompareInfo 


'This code produces the following output.
'
'Original      : Is AE or ae the same as Æ or æ?
'No options    : -------- ae the same as Æ -----
'           AE :                         b
'           ae :          b
'            Æ :                         b
'            æ :          b
'Ordinal       : -------- ae the same as Æ -----
'           AE :
'           ae :          b
'            Æ :                         b
'            æ :
'IgnoreCase    : -------- ae the same as Æ -----
'           AE :          f              l
'           ae :          f              l
'            Æ :          f              l
'            æ :          f              l
'
'Original      : Is U" or u" the same as Ü or ü?
'No options    : -------- u" the same as Ü -----
'           U" :                         b
'           u" :          b
'            Ü :                         b
'            ü :          b
'Ordinal       : -------- u" the same as Ü -----
'           U" :
'           u" :          b
'            Ü :                         b
'            ü :
'IgnoreCase    : -------- u" the same as Ü -----
'           U" :          f              l
'           u" :          f              l
'            Ü :          f              l
'            ü :          f              l

using System;
using System.Globalization;

public class Example
{

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {

      // Creates CompareInfo for the InvariantCulture.
      CompareInfo myComp = CultureInfo.InvariantCulture.CompareInfo;

      // iS is the starting index of the substring.
      int iS = 8;
      // iL is the length of the substring.
      int iL = 18;
      // myT1 and myT2 are the strings used for padding.
      String myT1 = new String('-', iS);
      String myT2;

      // Searches for the ligature Æ.
      String myStr = "Is AE or ae the same as Æ or æ?";
      myT2 = new String('-', myStr.Length - iS - iL);
      outputBlock.Text += "\n";
      outputBlock.Text += String.Format("Original      : {0}", myStr) + "\n";
      outputBlock.Text += String.Format("No options    : {0}{1}{2}", myT1, myStr.Substring(iS, iL), myT2) + "\n";
      PrintMarker(outputBlock, "           AE : ", myComp.IndexOf(myStr, "AE", iS, iL), myComp.LastIndexOf(myStr, "AE", iS + iL - 1, iL));
      PrintMarker(outputBlock, "           ae : ", myComp.IndexOf(myStr, "ae", iS, iL), myComp.LastIndexOf(myStr, "ae", iS + iL - 1, iL));
      PrintMarker(outputBlock, "            Æ : ", myComp.IndexOf(myStr, 'Æ', iS, iL), myComp.LastIndexOf(myStr, 'Æ', iS + iL - 1, iL));
      PrintMarker(outputBlock, "            æ : ", myComp.IndexOf(myStr, 'æ', iS, iL), myComp.LastIndexOf(myStr, 'æ', iS + iL - 1, iL));
      outputBlock.Text += String.Format("Ordinal       : {0}{1}{2}", myT1, myStr.Substring(iS, iL), myT2) + "\n";
      PrintMarker(outputBlock, "           AE : ", myComp.IndexOf(myStr, "AE", iS, iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "AE", iS + iL - 1, iL, CompareOptions.Ordinal));
      PrintMarker(outputBlock, "           ae : ", myComp.IndexOf(myStr, "ae", iS, iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "ae", iS + iL - 1, iL, CompareOptions.Ordinal));
      PrintMarker(outputBlock, "            Æ : ", myComp.IndexOf(myStr, 'Æ', iS, iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, 'Æ', iS + iL - 1, iL, CompareOptions.Ordinal));
      PrintMarker(outputBlock, "            æ : ", myComp.IndexOf(myStr, 'æ', iS, iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, 'æ', iS + iL - 1, iL, CompareOptions.Ordinal));
      outputBlock.Text += String.Format("IgnoreCase    : {0}{1}{2}", myT1, myStr.Substring(iS, iL), myT2) + "\n";
      PrintMarker(outputBlock, "           AE : ", myComp.IndexOf(myStr, "AE", iS, iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "AE", iS + iL - 1, iL, CompareOptions.IgnoreCase));
      PrintMarker(outputBlock, "           ae : ", myComp.IndexOf(myStr, "ae", iS, iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "ae", iS + iL - 1, iL, CompareOptions.IgnoreCase));
      PrintMarker(outputBlock, "            Æ : ", myComp.IndexOf(myStr, 'Æ', iS, iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, 'Æ', iS + iL - 1, iL, CompareOptions.IgnoreCase));
      PrintMarker(outputBlock, "            æ : ", myComp.IndexOf(myStr, 'æ', iS, iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, 'æ', iS + iL - 1, iL, CompareOptions.IgnoreCase));

      // Searches for the combining character sequence Latin capital letter U with diaeresis or Latin small letter u with diaeresis.
      myStr = "Is \u0055\u0308 or \u0075\u0308 the same as \u00DC or \u00FC?";
      myT2 = new String('-', myStr.Length - iS - iL);
      outputBlock.Text += "\n";
      outputBlock.Text += String.Format("Original      : {0}", myStr) + "\n";
      outputBlock.Text += String.Format("No options    : {0}{1}{2}", myT1, myStr.Substring(iS, iL), myT2) + "\n";
      PrintMarker(outputBlock, "           U\u0308 : ", myComp.IndexOf(myStr, "U\u0308", iS, iL), myComp.LastIndexOf(myStr, "U\u0308", iS + iL - 1, iL));
      PrintMarker(outputBlock, "           u\u0308 : ", myComp.IndexOf(myStr, "u\u0308", iS, iL), myComp.LastIndexOf(myStr, "u\u0308", iS + iL - 1, iL));
      PrintMarker(outputBlock, "            Ü : ", myComp.IndexOf(myStr, 'Ü', iS, iL), myComp.LastIndexOf(myStr, 'Ü', iS + iL - 1, iL));
      PrintMarker(outputBlock, "            ü : ", myComp.IndexOf(myStr, 'ü', iS, iL), myComp.LastIndexOf(myStr, 'ü', iS + iL - 1, iL));
      outputBlock.Text += String.Format("Ordinal       : {0}{1}{2}", myT1, myStr.Substring(iS, iL), myT2) + "\n";
      PrintMarker(outputBlock, "           U\u0308 : ", myComp.IndexOf(myStr, "U\u0308", iS, iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "U\u0308", iS + iL - 1, iL, CompareOptions.Ordinal));
      PrintMarker(outputBlock, "           u\u0308 : ", myComp.IndexOf(myStr, "u\u0308", iS, iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, "u\u0308", iS + iL - 1, iL, CompareOptions.Ordinal));
      PrintMarker(outputBlock, "            Ü : ", myComp.IndexOf(myStr, 'Ü', iS, iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, 'Ü', iS + iL - 1, iL, CompareOptions.Ordinal));
      PrintMarker(outputBlock, "            ü : ", myComp.IndexOf(myStr, 'ü', iS, iL, CompareOptions.Ordinal), myComp.LastIndexOf(myStr, 'ü', iS + iL - 1, iL, CompareOptions.Ordinal));
      outputBlock.Text += String.Format("IgnoreCase    : {0}{1}{2}", myT1, myStr.Substring(iS, iL), myT2) + "\n";
      PrintMarker(outputBlock, "           U\u0308 : ", myComp.IndexOf(myStr, "U\u0308", iS, iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "U\u0308", iS + iL - 1, iL, CompareOptions.IgnoreCase));
      PrintMarker(outputBlock, "           u\u0308 : ", myComp.IndexOf(myStr, "u\u0308", iS, iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, "u\u0308", iS + iL - 1, iL, CompareOptions.IgnoreCase));
      PrintMarker(outputBlock, "            Ü : ", myComp.IndexOf(myStr, 'Ü', iS, iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, 'Ü', iS + iL - 1, iL, CompareOptions.IgnoreCase));
      PrintMarker(outputBlock, "            ü : ", myComp.IndexOf(myStr, 'ü', iS, iL, CompareOptions.IgnoreCase), myComp.LastIndexOf(myStr, 'ü', iS + iL - 1, iL, CompareOptions.IgnoreCase));

   }

   public static void PrintMarker(System.Windows.Controls.TextBlock outputBlock, String Prefix, int First, int Last)
   {

      // Determines the size of the array to create.
      int mySize;
      if (Last > First)
         mySize = Last;
      else
         mySize = First;

      if (mySize > -1)
      {

         // Creates an array of Char to hold the markers.
         Char[] myCharArr = new Char[mySize + 1];

         // Inserts the appropriate markers.
         if (First > -1)
            myCharArr[First] = 'f';
         if (Last > -1)
            myCharArr[Last] = 'l';
         if (First == Last)
            myCharArr[First] = 'b';

         // Displays the array of Char as a String.
         outputBlock.Text += String.Format("{0}{1}", Prefix, new String(myCharArr)) + "\n";

      }
      else
         outputBlock.Text += Prefix + "\n";

   }

}


/*
This code produces the following output.

Original      : Is AE or ae the same as Æ or æ?
No options    : -------- ae the same as Æ -----
           AE :                         b
           ae :          b
            Æ :                         b
            æ :          b
Ordinal       : -------- ae the same as Æ -----
           AE :
           ae :          b
            Æ :                         b
            æ :
IgnoreCase    : -------- ae the same as Æ -----
           AE :          f              l
           ae :          f              l
            Æ :          f              l
            æ :          f              l

Original      : Is U" or u" the same as Ü or ü?
No options    : -------- u" the same as Ü -----
           U" :                         b
           u" :          b
            Ü :                         b
            ü :          b
Ordinal       : -------- u" the same as Ü -----
           U" :
           u" :          b
            Ü :                         b
            ü :
IgnoreCase    : -------- u" the same as Ü -----
           U" :          f              l
           u" :          f              l
            Ü :          f              l
            ü :          f              l

*/

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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CompareInfo.IndexOf Method (String, String, Int32, Int32, CompareOptions)

Syntax

Parameters

Return Value

Exceptions

Remarks

Examples

Version Information

Silverlight

Silverlight for Windows Phone

XNA Framework

Platforms

See Also

Reference

Additional resources