25.判断移动平台

function isAndroid() {
    var u = navigator.userAgent;
    if (u.indexOf('Android') > -1 || u.indexOf('Linux') > -1) { //安卓手机
        return true;
    }
    return false;
}

function isIOS() {
    var u = navigator.userAgent;
    var isiOS = !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/); //ios终端
    return isiOS;
}