How can you detect the version of a browser?

Question

I\'ve been searching around for code that would let me detect if the user visiting the website has Firefox 3 or 4. All I have found is code to detect the type of browser but

Answer 1

I use this to get de Name and number (int) of the version of the actual browser:

function getInfoBrowser() {
    var ua = navigator.userAgent, tem,
    M = ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
    if (/trident/i.test(M[1])) {
        tem = /\brv[ :]+(\d+)/g.exec(ua) || [];
        return { name: 'Explorer', version: parseInt((tem[1] || '')) };
    }
    if (M[1] === 'Chrome') {
        tem = ua.match(/\b(OPR|Edge)\/(\d+)/);
        if (tem != null) { let app = tem.slice(1).toString().split(','); return { name: app[0].replace('OPR', 'Opera'), version: parseInt(app[1]) }; }
    }
    M = M[2] ? [M[1], M[2]] : [navigator.appName, navigator.appVersion, '-?'];
    if ((tem = ua.match(/version\/(\d+)/i)) != null) M.splice(1, 1, tem[1]);
    return {
        name: M[0],
        version: parseInt(M[1])
    };
}

function getBrowser(){
  let info = getInfoBrowser();
  $("#i-name").html(info.name);
  $("#i-version").html(info.version);
}

Name: 

Version: 

This run in

Chrome ; Firefox ; Safari ; Internet Explorer (>= 9) ; Opera ; Edge

For me.