public void Drop() {

            Dictionary<string, string> book = new Dictionary<string, string>();
            book.Add( "请选择", "" );
            book.Add( "小说", "1" );
            book.Add( "诗歌", "2" );
            book.Add( "散文", "3" );
            book.Add( "戏剧", "4" );
            
            dropList( "book", book, null );

            Dictionary<string, string> music = new Dictionary<string, string>();
            music.Add( "请选择", "" );
            music.Add( "民谣", "1" );
            music.Add( "流行", "2" );
            music.Add( "摇滚", "3" );
            music.Add( "电子", "4" );
            
            dropList( "music", music, null );
        }