js 抢月饼第一步

基本思路：
1-获取 当前时间 与 抢购开始时间 时间差
2-获取抢购按钮 Dom元素
3-设置 setInterval定时函数，计算临近抢购时间前缩小定时器时间间隔

function panicCakes(){
    console.log("panic mooncakes");
    document.getElementById('J_LinkBuy').click();
}
//以抢下午12点的为例
var deadline=new Date(2016,10,18,12,0);
var panic=null,diffs=null;
var t=setInterval(function(){
    var now=new Date();
    console.log(deadline)
    console.log(now)
    var    diffms=deadline.getTime()-now.getTime();
    console.log(diffms)
    if(diffms<5001){
        console.log("开始加速...")
        panic=setInterval(panicCakes,50)
    }else{
        diffs=diffms/1000;
        console.log("剩余"+parseInt(diffs/60)+"分"+parseInt(diffs%60)+"秒")
    }
},5000)

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