public class WaitForFile
 {
  private WaitForFile()
  {
  }
  public static String Wait( String DirectoryToWatch )
  {    
   while( true )
   {
    String[] File = Directory.GetFiles( DirectoryToWatch , "*.*" );
    if( File.Length > 0 )
    {
     return File[0];
    }
    Thread.Sleep( 500 );
   }   
  }
 }