C#程序中创建、复制、移动、删除文件或文件夹的示例

创建文件或文件夹

您可通过编程方式在您的计算机上创建文件夹、子文件夹和子文件夹中的文件，并将数据写入文件。

public class CreateFileOrFolder
{
 static void Main()
 {
   string folderName = @"c:\Top-Level Folder";

string pathString = System.IO.Path.Combine(folderName, "SubFolder");

string pathString2 = @"c:\Top-Level Folder\SubFolder2";

System.IO.Directory.CreateDirectory(pathString);

string fileName = System.IO.Path.GetRandomFileName();

pathString = System.IO.Path.Combine(pathString, fileName);

Console.WriteLine("Path to my file: {0}\n", pathString);

if (!System.IO.File.Exists(pathString))
   {
     using (System.IO.FileStream fs = System.IO.File.Create(pathString))
     {
       for (byte i = 0; i < 100; i++)
       {
         fs.WriteByte(i);
       }
     }
   }
   else
   {
     Console.WriteLine("File \"{0}\" already exists.", fileName);
     return;
   }

try
   {
     byte[] readBuffer = System.IO.File.ReadAllBytes(pathString);
     foreach (byte b in readBuffer)
     {
       Console.Write(b + " ");
     }
     Console.WriteLine();
   }
   catch (System.IO.IOException e)
   {
     Console.WriteLine(e.Message);
   }

System.Console.WriteLine("Press any key to exit.");
   System.Console.ReadKey();
 }

}

输出：
Path to my file: c:\Top-Level Folder\SubFolder\ttxvauxe.vv0

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56
57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 8
3 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99

如果该文件夹已存在，则 CreateDirectory 不执行任何操作，且不会引发异常。但是，File.Create 用新的文件替换现有文件。该示例使用一个 if-else 语句阻止现有文件被替换。
通过在示例中做出以下更改，您可以根据具有某个名称的程序是否存在来指定不同的结果。如果该文件不存在，代码将创建一个文件。如果该文件存在，代码将把数据添加到该文件中。
指定一个非随机文件名。

// Comment out the following line.
//string fileName = System.IO.Path.GetRandomFileName();

// Replace that line with the following assignment.
string fileName = "MyNewFile.txt";

用以下代码中的 using 语句替换 if-else 语句。

using (System.IO.FileStream fs = new System.IO.FileStream(pathString, FileMode.Append))
{
 for (byte i = 0; i < 100; i++)
 {
   fs.WriteByte(i);
 }
}

运行该示例若干次以验证数据是否每次都添加到文件中。

复制、删除和移动文件和文件夹
以下示例说明如何使用 System.IO 命名空间中的 System.IO.File、System.IO.Directory、System.IO.FileInfo 和 System.IO.DirectoryInfo 类以同步方式复制、移动和删除文件和文件夹。 这些示例没有提供进度栏或其他任何用户界面。
。
示例
下面的示例演示如何复制文件和目录。

public class SimpleFileCopy
{
 static void Main()
 {
   string fileName = "test.txt";
   string sourcePath = @"C:\Users\Public\TestFolder";
   string targetPath = @"C:\Users\Public\TestFolder\SubDir";

// Use Path class to manipulate file and directory paths.
   string sourceFile = System.IO.Path.Combine(sourcePath, fileName);
   string destFile = System.IO.Path.Combine(targetPath, fileName);

// To copy a folder's contents to a new location:
   // Create a new target folder, if necessary.
   if (!System.IO.Directory.Exists(targetPath))
   {
     System.IO.Directory.CreateDirectory(targetPath);
   }

// To copy a file to another location and
   // overwrite the destination file if it already exists.
   System.IO.File.Copy(sourceFile, destFile, true);

// To copy all the files in one directory to another directory.
   // Get the files in the source folder. (To recursively iterate through
   // all subfolders under the current directory, see
   // "How to: Iterate Through a Directory Tree.")
   // Note: Check for target path was performed previously
   //    in this code example.
   if (System.IO.Directory.Exists(sourcePath))
   {
     string[] files = System.IO.Directory.GetFiles(sourcePath);

// Copy the files and overwrite destination files if they already exist.
     foreach (string s in files)
     {
       // Use static Path methods to extract only the file name from the path.
       fileName = System.IO.Path.GetFileName(s);
       destFile = System.IO.Path.Combine(targetPath, fileName);
       System.IO.File.Copy(s, destFile, true);
     }
   }
   else
   {
     Console.WriteLine("Source path does not exist!");
   }

// Keep console window open in debug mode.
   Console.WriteLine("Press any key to exit.");
   Console.ReadKey();
 }
}

下面的示例演示如何移动文件和目录。

public class SimpleFileMove
{
 static void Main()
 {
   string sourceFile = @"C:\Users\Public\public\test.txt";
   string destinationFile = @"C:\Users\Public\private\test.txt";

// To move a file or folder to a new location:
   System.IO.File.Move(sourceFile, destinationFile);

// To move an entire directory. To programmatically modify or combine
   // path strings, use the System.IO.Path class.
   System.IO.Directory.Move(@"C:\Users\Public\public\test\", @"C:\Users\Public\private");
 }
}

下面的示例演示如何删除文件和目录。

public class SimpleFileDelete
{
 static void Main()
 {
   // Delete a file by using File class static method...
   if(System.IO.File.Exists(@"C:\Users\Public\DeleteTest\test.txt"))
   {
     // Use a try block to catch IOExceptions, to
     // handle the case of the file already being
     // opened by another process.
     try
     {
       System.IO.File.Delete(@"C:\Users\Public\DeleteTest\test.txt");
     }
     catch (System.IO.IOException e)
     {
       Console.WriteLine(e.Message);
       return;
     }
   }

// ...or by using FileInfo instance method.
   System.IO.FileInfo fi = new System.IO.FileInfo(@"C:\Users\Public\DeleteTest\test2.txt");
   try
   {
     fi.Delete();
   }
   catch (System.IO.IOException e)
   {
     Console.WriteLine(e.Message);
   }

// Delete a directory. Must be writable or empty.
   try
   {
     System.IO.Directory.Delete(@"C:\Users\Public\DeleteTest");
   }
   catch (System.IO.IOException e)
   {
     Console.WriteLine(e.Message);
   }
   // Delete a directory and all subdirectories with Directory static method...
   if(System.IO.Directory.Exists(@"C:\Users\Public\DeleteTest"))
   {
     try
     {
       System.IO.Directory.Delete(@"C:\Users\Public\DeleteTest", true);
     }

catch (System.IO.IOException e)
     {
       Console.WriteLine(e.Message);
     }
   }

// ...or with DirectoryInfo instance method.
   System.IO.DirectoryInfo di = new System.IO.DirectoryInfo(@"C:\Users\Public\public");
   // Delete this dir and all subdirs.
   try
   {
     di.Delete(true);
   }
   catch (System.IO.IOException e)
   {
     Console.WriteLine(e.Message);
   }

}
}