FileSystemInfo.LastAccessTimeUtc 属性

定义

获取或设置上次访问当前文件或目录的时间,其格式为协调世界时 (UTC)。Gets or sets the time, in coordinated universal time (UTC), that the current file or directory was last accessed.

public:
 property DateTime LastAccessTimeUtc { DateTime get(); void set(DateTime value); };
[System.Runtime.InteropServices.ComVisible(false)]
public DateTime LastAccessTimeUtc { get; set; }
member this.LastAccessTimeUtc : DateTime with get, set
Public Property LastAccessTimeUtc As DateTime

属性值

上次访问当前文件或目录的 UTC 时间。The UTC time that the current file or directory was last accessed.

属性

异常

Refresh() 不能初始化数据。Refresh() cannot initialize the data.

当前操作系统不是 Windows NT 或更高版本。The current operating system is not Windows NT or later.

调用方试图设置无效的访问时间。The caller attempts to set an invalid access time.

注解

备注

此方法可能会返回不正确的值, 因为它使用的本机函数的值可能不会持续由操作系统进行更新。This method may return an inaccurate value because it uses native functions whose values may not be continuously updated by the operating system.

如果FileSystemInfo对象的当前LastAccessTimeUtc实例是从以下DirectoryInfo任一方法返回的, 则该属性的值将被预先缓存:The value of the LastAccessTimeUtc property is pre-cached if the current instance of the FileSystemInfo object was returned from any of the following DirectoryInfo methods:

若要获取最新值, 请Refresh调用方法。To get the latest value, call the Refresh method.

如果FileSystemInfo对象中描述的文件不存在, 则此属性返回12:00 年1月 1601 1 日午夜If the file described in the FileSystemInfo object does not exist, this property returns 12:00 midnight, January 1, 1601 A.D. 公元协调世界时 (UTC)。(C.E.) Coordinated Universal Time (UTC).

有关常见 i/o 任务的列表, 请参阅常见 I/o 任务For a list of common I/O tasks, see Common I/O Tasks.

安全性

FileIOPermission
用于设置上次访问时间。for setting the last access time. 关联的枚举:WriteAssociated enumeration: Write

适用于

另请参阅