这是一款使用jquery制作的九宫格抽奖转盘特效代码。该jquery九宫格抽奖转盘特效模拟手机端app的抽奖天天送豪礼页面,用户可以点击抽奖按钮来随机获取奖品。

使用方法

在页面中引入jquery.min.js文件。

<script src="js/jquery.min.js"></script>                                
                
HTML结构

该九宫格抽奖转盘特效使用的HTML结构是一个表格:

<div id="lottery">
    <table border="0" cellpadding="0" cellspacing="0">
        <tr>
            <td class="lottery-unit lottery-unit-0"><img src="img/1.jpg"><div class="mask"></div></td>
            <td class="lottery-unit lottery-unit-1"><img src="img/2.jpg"><div class="mask"></div></td>
            <td class="lottery-unit lottery-unit-2"><img src="img/3.jpg"><div class="mask"></div></td>
        </tr>
        <tr>
            <td class="lottery-unit lottery-unit-7"><img src="img/4.jpg"><div class="mask"></div></td>
            <td><a href="#"></a></td>
            <td class="lottery-unit lottery-unit-3"><img src="img/5.jpg"><div class="mask"></div></td>
        </tr>
        <tr>
            <td class="lottery-unit lottery-unit-6"><img src="img/6.jpg"><div class="mask"></div></td>
            <td class="lottery-unit lottery-unit-5"><img src="img/7.jpg"><div class="mask"></div></td>
            <td class="lottery-unit lottery-unit-4"><img src="img/8.jpg"><div class="mask"></div></td>
        </tr>
    </table>
</div>     
                
CSS样式

为九宫格抽奖转盘添加下面的CSS样式。

#lottery{width:570px;height:510px;margin:0px auto;border:4px solid #ba1809;}
#lottery table{background-color:yellow;}
#lottery table td{position:relative;width:190px;height:170px;text-align:center;color:#333;font-index:-999}
#lottery table td img{display:block;width:190px;height:170px;}
#lottery table td a{width:190px;height:170px;display:block;text-decoration:none;background:url(img/9.jpg) no-repeat top center;}
#lottery table td a:hover{background-image:url(img/11.jpg);}
#lottery table td.active .mask{display:block;}
.mask{
    width:100%;
    height:100%;
    position:absolute;
    left:0;
    top:0;
    background-color: rgba(252,211,4,0.5);
    display:none;
}              
                
JavaScript

在页面DOM元素加载完毕之后,使用下面的jquery代码来完成九宫格抽奖转盘的抽奖功能。

var lottery={
    index:-1,    //当前转动到哪个位置,起点位置
    count:0,    //总共有多少个位置
    timer:0,    //setTimeout的ID,用clearTimeout清除
    speed:20,    //初始转动速度
    times:0,    //转动次数
    cycle:50,    //转动基本次数:即至少需要转动多少次再进入抽奖环节
    prize:-1,    //中奖位置
    init:function(id){
        if ($("#"+id).find(".lottery-unit").length>0) {
            $lottery = $("#"+id);
            $units = $lottery.find(".lottery-unit");
            this.obj = $lottery;
            this.count = $units.length;
            $lottery.find(".lottery-unit-"+this.index).addClass("active");
        };
    },
    roll:function(){
        var index = this.index;
        var count = this.count;
        var lottery = this.obj;
        $(lottery).find(".lottery-unit-"+index).removeClass("active");
        index += 1;
        if (index>count-1) {
            index = 0;
        };
        $(lottery).find(".lottery-unit-"+index).addClass("active");
        this.index=index;
        return false;
    },
    stop:function(index){
        this.prize=index;
        return false;
    }
};

function roll(){
    lottery.times += 1;
    lottery.roll();//转动过程调用的是lottery的roll方法,这里是第一次调用初始化
    if (lottery.times > lottery.cycle+10 && lottery.prize==lottery.index) {
        clearTimeout(lottery.timer);
        lottery.prize=-1;
        lottery.times=0;
        click=false;
    }else{
        if (lottery.times<lottery.cycle) {
            lottery.speed -= 10;
        }else if(lottery.times==lottery.cycle) {
            var index = Math.random()*(lottery.count)|0;//中奖物品通过一个随机数生成
            lottery.prize = index;        
        }else{
            if (lottery.times > lottery.cycle+10 && ((lottery.prize==0 && lottery.index==7) || lottery.prize==lottery.index+1)) {
                lottery.speed += 110;
            }else{
                lottery.speed += 20;
            }
        }
        if (lottery.speed<40) {
            lottery.speed=40;
        };
        lottery.timer = setTimeout(roll,lottery.speed);//循环调用
    }
    return false;
}

var click=false;

window.onload=function(){
    lottery.init('lottery');
    $("#lottery a").click(function(){
        if (click) {//click控制一次抽奖过程中不能重复点击抽奖按钮,后面的点击不响应
            return false;
        }else{
            lottery.speed=100;
            roll();    //转圈过程不响应click事件,会将click置为false
            click=true; //一次抽奖完成后,设置click为true,可继续抽奖
            return false;
        }
    });
};