关于手机ios和安卓和pc的点击事件的兼容

var u = navigator.userAgent, app = navigator.appVersion;
var clickEvent;
var isAndroid = u.indexOf('Android') > -1 || u.indexOf('Linux') > -1; //android终端或者uc浏览器
var isiOS = !!u.match(/(i[^;]+;( U;)? CPU.+Mac OS X/); //ios终端
if(isiOS){
clickEvent = 'touchstart';
}else{
clickEvent= 'touchstart';
}

判断是什么机型