FileSystemInfo::LastWriteTime Property
Gets or sets the time when the current file or directory was last written to.
Assembly: mscorlib (in mscorlib.dll)
| Exception | Condition |
|---|---|
| IOException | Refresh cannot initialize the data. |
| PlatformNotSupportedException | The current operating system is not Windows NT or later. |
| ArgumentOutOfRangeException | The caller attempts to set an invalid write time. |
Note This method may return an inaccurate value, because it uses native functions whose values may not be continuously updated by the operating system.
The value of the LastWriteTime property is pre-cached if the current instance of the FileSystemInfo object was returned from any of the following DirectoryInfo methods:
To get the latest value, call the Refresh method.
If the file described in the FileSystemInfo object does not exist, this property will return 12:00 midnight, January 1, 1601 A.D. (C.E.) Coordinated Universal Time (UTC), adjusted to local time.
This property value is null if the file system containing the file does not support this information.
These operating systems do not support this property, and DirectoryInfo implementations of this property are not supported.
The following code example demonstrates the updating of the LastWriteTime property through a "touch" operation. In this example, the file is "touched", updating the CreationTime, LastAccessTime and LastWriteTime properties to the current date and time.
for setting the last write time. Associated enumeration: FileIOPermissionAccess::Write
Available since 10
.NET Framework
Available since 1.1
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0