navigator 判断移动端是Android还是iOS

let u = navigator.userAgent;

let isAndroid = u.indexOf('Android') > -1 || u.indexOf('Adr') > -1;

let isiOS = !!u.match(/(i[^;]+;( U;)? CPU.+Mac OS X/);

if(isAndroid){

alert('android');

}

if(isiOS){

alert('ios');

}