项目
11/18/2011

Convert.ToDouble Method (Byte)

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

Converts the value of the specified 8-bit unsigned integer to the equivalent double-precision floating point number.

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

Syntax

'Declaration
Public Shared Function ToDouble ( _
    value As Byte _
) As Double

public static double ToDouble(
    byte value
)

Parameters

value
Type: System.Byte
An 8-bit unsigned integer.

Return Value

Type: System.Double
The double-precision floating point number equivalent to the value of value.

Examples

The following code sample illustrates the conversion of a Byte value to a Double one, using ToDouble.

Public Sub ConvertDoubleByte(ByVal doubleVal As Double)
   Dim byteVal As Byte = 0

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

   ' Byte to Double conversion cannot overflow.
   doubleVal = System.Convert.ToDouble(byteVal)
   outputBlock.Text &= String.Format("{0} as a Double is: {1}.", _
                             byteVal, doubleVal) & vbCrLf
End Sub

public void ConvertDoubleByte(double doubleVal)
{
   byte byteVal = 0;

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

   // Byte to double conversion cannot overflow.
   doubleVal = System.Convert.ToDouble(byteVal);
   outputBlock.Text += String.Format("{0} as a double is: {1}.",
      byteVal, doubleVal) + "\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.

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