Partager via


DateTimeOffset.FromFileTime Method

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

Converts the specified Windows file time to an equivalent local time.

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

Syntax

'Declaration
Public Shared Function FromFileTime ( _
    fileTime As Long _
) As DateTimeOffset
public static DateTimeOffset FromFileTime(
    long fileTime
)

Parameters

  • fileTime
    Type: System.Int64
    A Windows file time, expressed in ticks.

Return Value

Type: System.DateTimeOffset
An object that represents the date and time of fileTime with the offset set to the local time offset.

Exceptions

Exception Condition
ArgumentOutOfRangeException

filetime is less than zero.

-or-

filetime is greater than DateTimeOffset.MaxValue.Ticks.

Remarks

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.

A Windows file time is directly accessible through the Windows API by calling the GetFileTime function, which returns a FILETIME structure. The single function parameter is the handle of the file whose file time information is to be retrieved. The file handle is retrieved by calling the CreateFile function. The FILETIME structure's dwHighDateTime member contains the four high-order bytes of the file time, and its dwLowDateTime member contains the four low-order bytes. The example that follows illustrates how to retrieve Windows file time values and convert them to DateTimeOffset values.

Windows file time values can also be created from DateTime values by calling the DateTime.ToFileTime and DateTime.ToFileTimeUtc methods, and from DateTimeOffset values by calling the DateTimeOffset.ToFileTime method.

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.