javascript固定时间操作器

function clock(timeout,willdo) {        var timer = 0;    var MPC = 0;    this.start = function () {        timer  = setInterval(onemDo, 100);        }    this.end = function () {        var result = MPC;        clearInterval(timer);        MPC = 0;        return result;    }    function onemDo() {        MPC++;        alert(MPC);        if (MPC > timeout)        {            willdo();            clearInterval(timer);            MPC = 0;        }    }}

如果某一个动作达到了timeout*100ms 则执行willdo方法，仅此而已。