方法：
function isMobile() {
var mobile_flag = false;
//根据userAgent判断是否是手机
if((navigator.userAgent.match(/(iPhone|iPod|Android|ios|iOS|iPad|WebOS|Symbian|Windows Phone|Phone)/i))) {
mobile_flag = true;
}
//根据屏幕分辨率判断是否是手机
var screen_width = window.screen.width;
var screen_height = window.screen.height;
if(screen_width < 500 && screen_height < 800){
mobile_flag = true;
}
return mobile_flag;
}
end.