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DateTime.FromFileTime Method

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

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

static DateTime FromFileTime (
	long long fileTime
public static DateTime FromFileTime (
	long fileTime
public static function FromFileTime (
	fileTime : long
) : DateTime



A Windows file time expressed in ticks.

Return Value

A DateTime object that represents a local time equivalent to the date and time represented by the fileTime parameter.

Exception typeCondition


fileTime is less than 0 or represents a time greater than MaxValue.

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 fileTime parameter specifies a file time expressed in 100-nanosecond ticks.

Starting with the .NET Framework version 2.0, the return value is a DateTime whose Kind property is Local.

The following code example demonstrates the FromFileTime method.

System::TimeSpan FileAge( long fileCreationTime )
   System::DateTime now = System::DateTime::Now;
      System::DateTime fCreationTime =
         System::DateTime::FromFileTime( fileCreationTime );
      System::TimeSpan fileAge = now.Subtract( fCreationTime );
      return fileAge;
   catch ( ArgumentOutOfRangeException^ ) 
      // fileCreationTime is not valid, so re-throw the exception.

public System.TimeSpan FileAge(long fileCreationTime) {

    System.DateTime now = System.DateTime.get_Now();
    try {
        System.DateTime fCreationTime = System.DateTime.
        System.TimeSpan fileAge = now.Subtract(fCreationTime);
        return fileAge;
    catch(ArgumentOutOfRangeException exp){
        // fileCreationTime is not valid, so re-throw the exception.
        throw new ArgumentOutOfRangeException()  ;
} //FileAge

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, 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