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Convert.ToByte Method (Double)

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

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

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

Syntax

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

public static byte ToByte(
    double value
)

Parameters

  • value
    Type: System.Double
    A double-precision floating point number.

Return Value

Type: System.Byte
value rounded to the nearest 8-bit signed integer. If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

Exceptions

Exception Condition
OverflowException

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

Examples

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

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.