共用方式為

  • 發行項

Convert.ToSingle 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 single-precision floating point number.

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

Syntax

'Declaration
Public Shared Function ToSingle ( _
    value As Double _
) As Single

public static float ToSingle(
    double value
)

Parameters

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

Return Value

Type: System.Single
A single-precision floating point number equivalent to the value of value.
value is rounded using rounding to nearest. For example, when rounded to two decimals, the value 2.345 becomes 2.34 and the value 2.355 becomes 2.36.

Examples

The following code sample illustrates the conversion of a Double to Single, using ToSingle.

Public Sub CovertDoubleFloat(ByVal doubleVal As Double)
   Dim singleVal As Single = 0

   ' Double to Single conversion cannot overflow.
   singleVal = System.Convert.ToSingle(doubleVal)
   outputBlock.Text &= String.Format("{0} as a Single is {1}", _
                             doubleVal, singleVal) & vbCrLf

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

public void CovertDoubleFloat(double doubleVal)
{
   float floatVal = 0;

   // Double to float conversion cannot overflow.
   floatVal = System.Convert.ToSingle(doubleVal);
   outputBlock.Text += String.Format("{0} as a float is {1}",
      doubleVal, floatVal) + "\n";

   // Conversion from float to double cannot overflow.
   doubleVal = System.Convert.ToDouble(floatVal);
   outputBlock.Text += String.Format("{0} as a double is: {1}",
      floatVal, 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.