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Convert.ToInt64 Method (Double)

Converts the value of the specified double-precision floating-point number to an equivalent 64-bit signed integer.

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

static member ToInt64 : 
        value:float -> int64 


Type: System.Double
The double-precision floating-point number to convert.

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.


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

The following example attempts to convert each element in an array of Double values to a long integer.

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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