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);
    }

  }
}