audioDom.oncanplaythrough = function(){

var msecond = this.duration;//获得整个音乐的长度

var m = parseInt(msecond/60);//分

var s = parseInt(msecond%60);//秒

var ms = (m<10 ? ("0"+m):m)+":"+(s<10 ? ("0"+s):s);

document.getElementById("time").innerHTML = ms;

};