共用方式為


Convert.ToByte Method (Int64)

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

Converts the value of the specified 64-bit signed integer to an equivalent 8-bit unsigned integer.

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

Syntax

'Declaration
Public Shared Function ToByte ( _
    value As Long _
) As Byte
public static byte ToByte(
    long value
)

Parameters

Return Value

Type: System.Byte
An 8-bit unsigned integer equivalent to the value of value.

Exceptions

Exception Condition
OverflowException

value is less than Byte.MinValue or greater than Byte.MaxValue.

Examples

The following code sample illustrates the use of ToByte, converting an Int64 (long) value to a Byte :

Public Sub ConvertLongByte(ByVal longVal As Long)

   Dim byteVal As Byte = 0

   ' A conversion from Long to Byte can overflow.
   Try
      byteVal = System.Convert.ToByte(longVal)
      outputBlock.Text &= String.Format("{0} as a Byte is {1}", _
                                longVal, byteVal) & vbCrLf
   Catch exception As System.OverflowException
      outputBlock.Text &= String.Format( _
          "Overflow in Long-to-Byte conversion.") & vbCrLf
   End Try

   ' A conversion from Byte to Long cannot overflow.
   longVal = System.Convert.ToInt64(byteVal)
   outputBlock.Text &= String.Format("{0} as an Long is {1}", _
                             byteVal, longVal) & vbCrLf
End Sub
public void ConvertLongByte(long longVal)
{
   byte byteVal = 0;

   // A conversion from Long to byte can overflow.
   try
   {
      byteVal = System.Convert.ToByte(longVal);
      outputBlock.Text += String.Format("{0} as a byte is {1}",
         longVal, byteVal) + "\n";
   }
   catch (System.OverflowException)
   {
      outputBlock.Text += String.Format(
         "Overflow in long-to-byte conversion.") + "\n";
   }

   // A conversion from Byte to long cannot overflow.
   longVal = System.Convert.ToInt64(byteVal);
   outputBlock.Text += String.Format("{0} as an Int64 is {1}",
      byteVal, longVal) + "\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.