using   System;   
  using   System.IO;   
    
  class   Test     
  {   
          public   static   void   Main()     
          {   
                  string   path   =   @"c:\temp\MyTest.txt";   
                  string   path2   =   path   +   "temp";   
    
                  try     
                  {   
                          //   Create   the   file   and   clean   up   handles.   
                          using   (FileStream   fs   =   File.Create(path))   {}   ///创建文件
    
                          
                          File.Delete(path2);    ////删除文件
    
                          //   Copy   the   file.   
                          File.Copy(path,   path2);   ////复制文件
                          Console.WriteLine("{0}   copied   to   {1}",   path,   path2);   
    
                          //   Try   to   copy   the   same   file   again,   which   should   succeed.   
                          File.Copy(path,   path2,   true);   
                          Console.WriteLine("The   second   Copy   operation   succeeded,   which   was   expected.");   
                  }     
    
                  catch     
                  {   
                          Console.WriteLine("Double   copy   is   not   allowed,   which   was   not   expected.");   
                  }   
          }  











//////////////////////
 private void btncopy_Click(object sender, EventArgs e)
	        {
	            openfile.FileName = null;
	            //显示打开文件对话框
	            if (openfile.ShowDialog() == DialogResult.OK)
	            {
	                //获取目标文件
	                string firstpath = openfile.FileName;
	                savefile.FileName = "";
	                //显示保存文件对话框
	                if (savefile.ShowDialog() == DialogResult.OK)
	                {
	                    //获取新文件路径
	                    string newpath = savefile.FileName;
	                    if (File.Exists(newpath))
	                        File.Delete(newpath);
	                    //拷贝文件
	                    File.Copy(firstpath, newpath, true);
	                    MessageBox.Show("复制成功！");
	                }
	            }