Convert.ToInt64 Method (Single)

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)

Public Shared Function ToInt64 ( _
	value As Single _
) As Long
Dim value As Single
Dim returnValue As Long

returnValue = Convert.ToInt64(value)
public static long ToInt64 (
	float value
public static function ToInt64 (
	value : float
) : long



A single-precision floating point number.

Return Value

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.

Exception typeCondition


value is greater than Int64.MaxValue or less than Int64.MinValue.

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)
    System.Console.WriteLine("{0} as a float is {1}", _
                              longVal, floatVal)

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

public void ConvertLongFloat(long longVal)
    float floatVal;

    // A conversion from Long to float cannot overflow.
    floatVal = System.Convert.ToSingle(longVal);
    System.Console.WriteLine("{0} as a float is {1}", 

    // A conversion from float to long can overflow.
    try {        
        longVal = System.Convert.ToInt64(floatVal);
        System.Console.WriteLine("{0} as a long is {1}", 
    catch (System.OverflowException exp) {        
        System.Console.WriteLine("Overflow in float-to-long conversion.");
} //ConvertLongFloat

Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

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