/// 删除文件和目录
public class Cleaner

{

   ///
   /// 删除指定目录以及该目录下所有文件
   ///
   /// 欲删除文件或者目录的路径
 
   public static void Clean ( string dir )

{
  
       CleanFiles ( dir );//第一次删除文件
  
       CleanFiles ( dir );//第二次删除目录
 
   }


private static void CleanFiles( string dir)

{
 
       if ( !Directory.Exists ( dir ) ) 
  
      {
          File.Delete ( dir );
          return;
  
      }
  
      else

    {

      string[] dirs = Directory.GetDirectories ( dir );

     string[] files = Directory.GetFiles ( dir );


   if ( 0 != dirs.Length )
     
     {
       
      foreach ( string subDir in dirs )
         
      {
           
       if ( null == Directory.GetFiles( subDir ) )
            
       {
                         Directory.Delete( subDir );
                
        return;
            
       }
            
       else CleanFiles ( subDir );
        
      }
     
     }
   
     if ( 0 != files.Length )
          {
     
      foreach ( string file in files )
      
      {
       
       File.Delete ( file );
               }
    
     }
    
     else Directory.Delete( dir );
   
    }

   }
}

foreach ( string subDir in dirs )
         
      {
           
       if ( null == Directory.GetFiles( subDir )   && subDir == "aaa.txt")
            
       {
                         Directory.Delete( subDir );
                
        return;
            
       }
            
       else CleanFiles ( subDir );
        
      }