//是否手机端判断
var ua = navigator.userAgent;
var ipad = ua.match(/(iPad).*OS\s([\d_]+)/),
isIphone = !ipad && ua.match(/(iPhone\sOS)\s([\d_]+)/),
isAndroid = ua.match(/(Android)\s+([\d.]+)/),
isMobile = isIphone || isAndroid;