Directory.SetLastWriteTime(String, DateTime) 方法
定义
重要
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设置上次写入目录的日期和时间。
public:
static void SetLastWriteTime(System::String ^ path, DateTime lastWriteTime);public static void SetLastWriteTime (string path, DateTime lastWriteTime);static member SetLastWriteTime : string * DateTime -> unitPublic Shared Sub SetLastWriteTime (path As String, lastWriteTime As DateTime)参数
- path
- String
目录的路径。
- lastWriteTime
- DateTime
上次写入目录的日期和时间。 该值用本地时间表示。
例外
找不到 path（例如，目录不存在或在未映射的驱动器上）。
找不到 path（例如，目录不存在或在未映射的驱动器上）。
.NET Framework 和 2.1 之前的 .NET Core 版本：path是一个零长度字符串，仅包含空格，或者包含一个或多个无效字符。 你可以使用 GetInvalidPathChars() 方法查询无效字符。
path 为 null。
指定的路径和/或文件名超过了系统定义的最大长度。
调用方没有所要求的权限。
当前操作系统不是 Windows NT 或更高版本。
lastWriteTime 指定一个超出该操作允许的日期或时间范围的值。
示例
以下示例演示如何使用 SetLastWriteTime。
using namespace System;
using namespace System::IO;
void main()
{
try
{
String^ path = "c:\\MyDir";
if ( !Directory::Exists( path ) )
{
Directory::CreateDirectory( path );
}
else
{
// Take an action that will affect the write time.
Directory::SetLastWriteTime( path, DateTime(1985,4,3) );
}
// Get the last write time of a well-known directory.
DateTime dt = Directory::GetLastWriteTime( path );
Console::WriteLine( "The last write time for this directory was {0}", dt );
//Update the last write time.
Directory::SetLastWriteTime( path, DateTime::Now );
dt = Directory::GetLastWriteTime( path );
Console::WriteLine( "The last write time for this directory was {0}", dt );
}
catch ( Exception^ e )
{
Console::WriteLine( "The process failed: {0}", e );
}
}
using System;
using System.IO;
class Test
{
public static void Main()
{
try
{
string path = @"c:\MyDir";
if (!Directory.Exists(path))
{
Directory.CreateDirectory(path);
}
else
{
// Take an action that will affect the write time.
Directory.SetLastWriteTime(path, new DateTime(1985,4,3));
}
// Get the last write time of a well-known directory.
DateTime dt = Directory.GetLastWriteTime(path);
Console.WriteLine("The last write time for this directory was {0}", dt);
//Update the last write time.
Directory.SetLastWriteTime(path, DateTime.Now);
dt = Directory.GetLastWriteTime(path);
Console.WriteLine("The last write time for this directory was {0}", dt);
}
catch (Exception e)
{
Console.WriteLine("The process failed: {0}", e.ToString());
}
}
}
open System
open System.IO
try
let path = @"c:\MyDir"
if not (Directory.Exists path) then
Directory.CreateDirectory path |> ignore
else
// Take an action that will affect the write time.
Directory.SetLastWriteTime(path, DateTime(1985, 4, 3))
// Get the last write time of a well-known directory.
let dt = Directory.GetLastWriteTime path
printfn $"The last write time for this directory was {dt}"
//Update the last write time.
Directory.SetLastWriteTime(path, DateTime.Now)
let dt = Directory.GetLastWriteTime path
printfn $"The last write time for this directory was {dt}"
with e ->
printfn $"The process failed: {e}"
Imports System.IO
Public Class Test
Public Shared Sub Main()
Try
Dim path As String = "c:\MyDir"
If Directory.Exists(path) = False Then
Directory.CreateDirectory(path)
Else
' Take an action that will affect the write time.
Directory.SetLastWriteTime(path, New DateTime(1985, 4, 3))
End If
'Get the last write time of a well-known directory.
Dim dt As DateTime = Directory.GetLastWriteTime(path)
Console.WriteLine("The last write time for this directory was {0}", dt)
'Update the last write time.
Directory.SetLastWriteTime(path, DateTime.Now)
dt = Directory.GetLastWriteTime(path)
Console.WriteLine("The last write time for this directory was {0}", dt)
Catch e As Exception
Console.WriteLine("The process failed: {0}", e.ToString())
End Try
End Sub
End Class
注解
允许 path 参数指定相对或绝对路径信息。 相对路径信息解释为相对于当前工作目录。 若要获取当前工作目录，请参阅 GetCurrentDirectory。
参数的 path 区分大小写对应于运行代码的文件系统的区分大小写。 例如，它在 NTFS 上不区分大小写， (默认 Windows 文件系统) ，Linux 文件系统上区分大小写。
有关常见 I/O 任务的列表，请参阅 常见 I/O 任务。
