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Convert.ToInt64 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 64-bit signed integer.

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

Syntax

'Declaration
Public Shared Function ToInt64 ( _
    value As Single _
) As Long

public static long ToInt64(
    float value
)

Parameters

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

Return Value

Type: System.Int64
value rounded to the nearest 64-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 Int64.MaxValue or less than Int64.MinValue.

Examples

The following code sample illustrates the conversion of a Single value to an Int64, using ToInt64.

Public Sub ConvertLongFloat(ByVal longVal As Long)

   Dim floatVal As Single

   ' A conversion from Long to float cannot overflow.
   floatVal = System.Convert.ToSingle(longVal)
   outputBlock.Text &= String.Format("{0} as a float is {1}", _
                             longVal, floatVal) & vbCrLf

   ' A conversion from float to long can overflow.
   Try
      longVal = System.Convert.ToInt64(floatVal)
      outputBlock.Text &= String.Format("{0} as a Long is {1}", _
                                floatVal, longVal) & vbCrLf
   Catch exception As System.OverflowException
      outputBlock.Text &= String.Format( _
          "Overflow in float-to-long conversion.") & vbCrLf
   End Try
End Sub

public void ConvertLongFloat(long longVal)
{
   float floatVal;

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

   // A conversion from float to long can overflow.
   try
   {
      longVal = System.Convert.ToInt64(floatVal);
      outputBlock.Text += String.Format("{0} as a long is {1}",
         floatVal, longVal) + "\n";
   }
   catch (System.OverflowException)
   {
      outputBlock.Text += String.Format(
         "Overflow in float-to-long conversion.") + "\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.