//获得长路径的相对短路径名称          [DllImport("kernel32.dll", CharSet = CharSet.Auto)]          public static extern uint GetShortPathName(string lpszLongPath, StringBuilder lpszShortPath, int cchBuffer);          //实现文件拷贝，递归逐文件拷贝          private void DirectoryCopy(string sourceDir, string targetDir)          {                                if (!Directory.Exists(sourceDir))              {                  DialogResult OKButtonDown = MessageBox.Show("需要备份的路径不存在，请查看！", "备份失败", MessageBoxButtons.OK, MessageBoxIcon.Warning);                  if (DialogResult.OK == OKButtonDown)                  {                      Application.Exit();                  }              }                             string sourceFolderName = sourceDir.Replace(Directory.GetParent(sourceDir).ToString(), "").Replace(Path.DirectorySeparatorChar.ToString(), "");                 if (sourceDir == targetDir + sourceFolderName)              {                  DialogResult OKButtonDown = MessageBox.Show("备份的目标路径和原路径相同，不需要备份！", "备份失败", MessageBoxButtons.OK, MessageBoxIcon.Warning);                  if (DialogResult.OK == OKButtonDown)                  {                      Application.Exit();                  }                  }                 //得到要复制到的路径              string tagetPath = targetDir + Path.DirectorySeparatorChar.ToString() + sourceFolderName;                    //检查目标路径              if (Directory.Exists(tagetPath))              {                  DialogResult OKButtonDown = MessageBox.Show("备份的目标路径已经存在，点击是将删除目标并备份，点击否将覆盖并备份", "请查看", MessageBoxButtons.YesNoCancel, MessageBoxIcon.Warning);                  if (DialogResult.Yes == OKButtonDown)                  {                      Directory.Delete(tagetPath, true);                      //return;                  }                  else if (DialogResult.No == OKButtonDown)                  {                      //复制文件                      string[] files1 = Directory.GetFiles(sourceDir);                      for (int i = 0; i < files1.Length; i++)                      {                             File.Copy(files1[i], tagetPath + Path.DirectorySeparatorChar.ToString() + Path.GetFileName(files1[i]), true);                      }                      //复制目录                      string[] dires1 = Directory.GetDirectories(sourceDir);                      for (int j = 0; j < dires1.Length; j++)                      {                          DirectoryCopy(dires1[j], tagetPath);                      }                      return;                  }                  else if (DialogResult.Cancel == OKButtonDown)                  {                      Application.Exit();                     }                 }                            StringBuilder _shortPath1 = new StringBuilder(255);              uint result1 = GetShortPathName(tagetPath, _shortPath1, 255);              string MyShortPath1 = _shortPath1.ToString();              if (0 == result1)              {                  Directory.CreateDirectory(tagetPath);              }              else              {                  Directory.CreateDirectory(MyShortPath1);              }              //复制文件              string[] files3 = Directory.GetFiles(sourceDir);              for (int i = 0; i < files3.Length; i++)              {                  //string longPath = tagetPath + Path.DirectorySeparatorChar.ToString() + Path.GetFileName(files3[i]);                  //StringBuilder _shortPath = new StringBuilder(255);                  //uint result = GetShortPathName(longPath, _shortPath, 255);                  //string MyShortPath = _shortPath.ToString();                  File.Copy(files3[i],/*MyShortPath/tagetPath + Path.DirectorySeparatorChar.ToString() + Path.GetFileName(files3[i]), true);              }              //复制目录              string[] dires3 = Directory.GetDirectories(sourceDir);              for (int j = 0; j < dires3.Length; j++)              {                  string longPath = dires3[j];                  StringBuilder _shortPath = new StringBuilder(255);                  uint result = GetShortPathName(longPath, _shortPath, 255);                  string MyShortPath = _shortPath.ToString();                     DirectoryCopy(MyShortPath, tagetPath);              }          }