实现 网页自动检测当前所处的设备是电脑还是手机从而实现对应PC端和手机端的不同效果

function IsPC() {
        var userAgentInfo = navigator.userAgent;
        var Agents = ["Android", "iPhone",
            "SymbianOS", "Windows Phone",
            "iPad", "iPod"];
        var flag = true;
        for (var v = 0; v < Agents.length; v++) {
            if (userAgentInfo.indexOf(Agents[v]) > 0) {
                flag = false;
                break;
            }
        }
        return flag;
    }

    var flag = IsPC(); //true为PC端，false为手机端
    window.function () {
        console.log(flag);
        if(flag){
            //pc端时响应
		}else {
            document.getElementById('web').style.display='none';
            document.getElementById('phone').style.display='block'
		}
    }