JS judges UA

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var browser = {
    versions: function () {
        var u = navigator.userAgent, app = navigator.appVersion;
        return { //Mobile terminal browser version information
            trident: u.indexOf('Trident') > -1, //IE kernel
            presto: u.indexOf('Presto') > -1, //opera kernel
            webKit: u.indexOf('AppleWebKit') > -1, //Apple, Google kernel
            gecko: u.indexOf('Gecko') > -1 && u.indexOf('KHTML') == -1, //Firefox kernel
            mobile: !!u.match(/AppleWebKit.*Mobile.*/), //Whether it is a mobile terminal
            ios: !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/), //ios终端
            android: u.indexOf('Android') > -1 || u.indexOf('Linux') > -1, //android terminal or uc browser
            iPhone: u.indexOf('iPhone') > -1, //whether it is an iPhone or QQHD browser
            iPad: u.indexOf('iPad') > -1, //whether iPad
            webApp: u.indexOf('Safari') == -1 //Whether the web should be a program, no header and bottom
        };
    }(),
    language: (navigator.browserLanguage || navigator.language).toLowerCase()
}
if (browser.versions.mobile) {//Determine whether the mobile device is open. browser code is below
    var ua = navigator.userAgent.toLowerCase();//Get the object for judgment
    if (ua.match(/MicroMessenger/i) == "micromessenger") {
        //Open in WeChat
    }
    if (ua.match(/WeiBo/i) == "weibo") {
        //Open in Sina Weibo client
    }
    if (ua.match(/QQ/i) == "qq") {
        //Open in QQ space
    }
    if (browser.versions.ios) {
        //Whether to open in IOS browser
    }
    if(browser.versions.android){
        //Whether to open in Android browser
    }
}else{
    //Otherwise, the PC browser is opened
}