Udostępnij za pośrednictwem

  • Artykuł

Convert.ToByte Method (Object)

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

Converts the value of the specified Object to an 8-bit unsigned integer.

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

Syntax

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

public static byte ToByte(
    Object 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
InvalidCastException

value does not implement IConvertible.

Remarks

If value is not nulla null reference (Nothing in Visual Basic), this method wraps a call to the IConvertible.ToByte implementation of the underlying type of value.

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.