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Convert.ToDouble Method (Single)

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

Converts the value of the specified single-precision floating point number to an equivalent double-precision floating point number.

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

Syntax

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

public static double ToDouble(
    float value
)

Parameters

  • value
    Type: System.Single
    A single-precision floating point number.

Return Value

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

Examples

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

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.