js判斷手機是安卓還是ios

//點擊下載按鈕判斷
appDown() {
    var u = navigator.userAgent;
    var isiOS = !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/);
    var isAndroid = u.indexOf('Android') > -1 || u.indexOf('Adr') > -1; //android終端
    if(isiOS){
        window.location.href = '安卓下載地址'
    }else if(isAndroid){
        window.location.href = '安卓下載地址'
    }
},