iphoneX 的判断

function isIPhoneX(){
            var u = navigator.userAgent;
            var isIOS = !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/); //ios终端
            if (isIOS) {        
                if (screen.height == 812 && screen.width == 375){
                // iphoneX的适配
                    }
                }else{
                    //不是iphoneX
                } 
            }
        }