• Artículo

Convert.ToByte Method (String)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Converts the specified String representation of a number to an equivalent 8-bit unsigned integer.

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

Syntax

'Declaration
Public Shared Function ToByte ( _
    value As String _
) As Byte

public static byte ToByte(
    string value
)

Parameters

Return Value

Type: System.Byte
An 8-bit unsigned integer equivalent to the value of value.
-or-
Zero if value is nulla null reference (Nothing in Visual Basic).

Exceptions

Exception Condition
FormatException

value does not consist of an optional sign followed by a sequence of digits (zero through nine).
OverflowException

value represents a number less than MinValue or greater than MaxValue.

Remarks

If you prefer not to handle an exception if the conversion fails, you can call the Byte.TryParse method instead. It returns a Boolean value that indicates whether the conversion succeeded or failed.

Examples

The following code sample illustrates the use of ToByte, converting a String value to a Byte :

Public Sub ConvertStringByte(ByVal stringVal As String)
   Dim byteVal As Byte = 0

   Try
      byteVal = System.Convert.ToByte(stringVal)
      outputBlock.Text &= String.Format("{0} as a byte is: {1}", _
                                stringVal, byteVal) & vbCrLf
   Catch exception As System.OverflowException
      outputBlock.Text &= String.Format( _
          "Overflow in string-to-byte conversion.") & vbCrLf
   Catch exception As System.FormatException
      outputBlock.Text &= String.Format( _
          "The String is not formatted as a Byte.") & vbCrLf
   Catch exception As System.ArgumentException
      outputBlock.Text &= "The String is null." & vbCrLf
   End Try

   'The conversion from byte to string is always valid.
   stringVal = System.Convert.ToString(byteVal)
   outputBlock.Text &= String.Format("{0} as a string is {1}", _
                             byteVal, stringVal) & vbCrLf
End Sub

public void ConvertStringByte(string stringVal)
{
   byte byteVal = 0;

   try
   {
      byteVal = System.Convert.ToByte(stringVal);
      outputBlock.Text += String.Format("{0} as a byte is: {1}",
         stringVal, byteVal) + "\n";
   }
   catch (System.OverflowException)
   {
      outputBlock.Text += String.Format(
         "Conversion from string to byte overflowed.") + "\n";
   }
   catch (System.FormatException)
   {
      outputBlock.Text += String.Format(
         "The string is not formatted as a byte.") + "\n";
   }
   catch (System.ArgumentNullException)
   {
      outputBlock.Text += String.Format(
         "The string is null.") + "\n";
   }

   //The conversion from byte to string is always valid.
   stringVal = System.Convert.ToString(byteVal);
   outputBlock.Text += String.Format("{0} as a string is {1}",
      byteVal, stringVal) + "\n";
}

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.