File.GetLastWriteTimeUtc(String)是一个内置的File类方法,该方法用于以协调世界时(UTC)返回最后一次写入指定文件或目录的日期和时间。
句法:
public static DateTime GetLastWriteTimeUtc (string path);
参数:该函数接受如下所示的参数:
- path: This is the specified file path.
例外情况:
- UnauthorizedAccessException:调用者没有所需的权限。
- ArgumentException:路径是长度为零的字符串,仅包含空格,或者由InvalidPathChars定义的一个或多个无效字符。
- ArgumentNullException:路径为null。
- PathTooLongException:给定的路径,文件名或两者都超过了系统定义的最大长度。
- NotSupportedException:路径格式无效。
返回值:以协调世界时(UTC)返回上次写入指定文件或目录的日期和时间。
下面是说明File.GetLastWriteTimeUtc(String)方法的程序。
程序1:在运行下面的代码之前,将创建一个文件file.txt ,其内容如下所示:
CSharp
// C# program to illustrate the usage
// of File.GetLastWriteTimeUtc(String) method
// Using System and System.IO namespaces
using System;
using System.IO;
class GFG {
public static void Main()
{
// Specifying a file
string myfile = @"file.txt";
// Calling GetLastWriteTimeUtc() function
DateTime dt = File.GetLastWriteTimeUtc(myfile);
// Getting the last write time in UTC
Console.WriteLine("The last write time in "+
"UTC for this file was {0}.", dt);
}
}
CSharp
// C# program to illustrate the usage
// of File.GetLastWriteTimeUtc(String) method
// Using System and System.IO namespaces
using System;
using System.IO;
class GFG {
public static void Main()
{
// Specifying a file
string myfile = @"file.txt";
// Setting the date
File.SetLastWriteTime(myfile, new DateTime(2020, 4, 3));
// Calling GetLastWriteTimeUtc() function
DateTime dt = File.GetLastWriteTimeUtc(myfile);
// Getting the last write time in UTC
Console.WriteLine("The last write time in"+
" UTC for this file was {0}.", dt);
}
}
执行中:
The last write time in UTC for this file was 4/3/2020 12:00:00 AM.
程序2:在运行下面的代码之前,创建了一个文件,如下所示:
尖锐的
// C# program to illustrate the usage
// of File.GetLastWriteTimeUtc(String) method
// Using System and System.IO namespaces
using System;
using System.IO;
class GFG {
public static void Main()
{
// Specifying a file
string myfile = @"file.txt";
// Setting the date
File.SetLastWriteTime(myfile, new DateTime(2020, 4, 3));
// Calling GetLastWriteTimeUtc() function
DateTime dt = File.GetLastWriteTimeUtc(myfile);
// Getting the last write time in UTC
Console.WriteLine("The last write time in"+
" UTC for this file was {0}.", dt);
}
}
执行中:
The last write time in UTC for this file was 4/3/2020 12:00:00 AM.