js 抽奖转盘实现

今天用js实现转盘抽奖功能，从后台返回的值可以固定转盘选择停止的任意位置

实现代码如下：

js：

<script>
        var auto, count = , i = ;//auto:时间对象 count：计数器 ，i ： 计数器
        var resultCode = "";//后台返回的结果的值
        var arry = [ "", "", "", "", "", "", "",""]; //返回值的数组，图片以数组中的数字命名
        function turn() {
            /// <summary>
            /// 转盘旋转
            /// </summary>
            i = (i == arry.length - ) ?  : i + ;
            $("#imgTurn").attr("src", "/Content/Images/" + arry[i] + ".png");

            //以下调整可以设置转盘转速
            if (count < ) {
                auto = setTimeout(turn, );
            } else if (count >=  && count < ) {
                auto = setTimeout(turn, );
            } else if (count >=  && count < ) {
                auto = setTimeout(turn, );
            } else if (count >=  && count < ) {
                auto = setTimeout(turn, );
            } else if (count >=  && count < ) {
                auto = setTimeout(turn, );
            }
            else {
                auto = setTimeout(turn, );
            }
            if (arry[i] == resultCode) {
                //当等于后台返回的值的时候停止转
                count = ;
                resultCode = ;
                clearTimeout(auto);

                $("#but_bulliondraw").bind("click", fun);

                return;
            }
            count += ;
        }

        function beginTurn() {
            /// <summary>
            /// 开始旋转
            /// </summary>
            /// <returns type=""></returns>
            if (count == ) {
                $("#imgTurn").attr("src", "/Content/Images/" + arry[i] + ".png");
                turn();
                return true;
            } else {
                return false;
            }
        }

        $(function () {
            //点击开始旋转
            $("#but_bulliondraw").bind("click", fun);
        });
        var fun = function () {
            $("#but_bulliondraw").unbind("click");
            if (beginTurn()) {
                //这里可以从后台请求返回的值，赋值给resultCode
                setTimeout(function () { resultCode =  }, );
            }
        };
    </script>

html代码：

 <div style="margin:0 auto; width:500px;">
      <p>
          <img src="/Content/Images/orderedList0.png" id="imgTurn" />@*默认有一张全部亮的图片*@
      </p>
        <input type="button" id="but_bulliondraw" value="开始抽奖" />
    </div>