ToFileTime Method

DateTimeOffset.ToFileTime Method

Converts the value of the current DateTimeOffset object to a Windows file time.

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

public function ToFileTime() : long

Return Value

Type: System.Int64
The value of the current DateTimeOffset object, expressed as a Windows file time.


The resulting file time would represent a date and time before midnight on January 1, 1601 C.E. Coordinated Universal Time (UTC).

A Windows file time is a 64-bit value that represents the number of 100-nanosecond intervals that have elapsed since 12:00 midnight, January 1, 1601 A.D. (C.E.) Coordinated Universal Time (UTC). Windows uses a file time to record when an application creates, accesses, or writes to a file.

The ToFileTime method converts the current DateTimeOffset object's date and time to UTC before it performs the conversion. In other words, calling the ToFileTime method is equivalent to the following method call:



[Visual Basic]


Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

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

.NET Framework

Supported in: 3.5 SP1, 3.0 SP1, 2.0 SP1

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