浏览器JavaScript库提供了此功能。

if (bowser.msie && bowser.version <= 6) {
  alert('Hello China');
}

它似乎保养得很好。

<script type="text/javascript">
var version = navigator.appVersion;
alert(version);
</script>

我用ASP代码做了一个检测浏览器，浏览器版本，OS和OS版本的脚本。 我在ASP中这样做的原因是因为我想将数据存储在日志数据库中。 所以我必须检测浏览器服务器端。

代码如下:

on error resume next
ua = lcase(Request.ServerVariables("HTTP_USER_AGENT"))
moz = instr(ua,"mozilla")  
ffx = instr(ua,"firefox")  
saf = instr(ua,"safari")
crm = instr(ua,"chrome") 
max = instr(ua,"maxthon") 
opr = instr(ua,"opera")
ie4 = instr(ua,"msie 4") 
ie5 = instr(ua,"msie 5") 
ie6 = instr(ua,"msie 6") 
ie7 = instr(ua,"msie 7") 
ie8 = instr(ua,"trident/4.0")
ie9 = instr(ua,"trident/5.0")

if moz>0 then 
    BrowserType = "Mozilla"
    BrVer = mid(ua,moz+8,(instr(moz,ua," ")-(moz+8)))
end if
if ffx>0 then 
    BrowserType = "FireFox"
    BrVer = mid(ua,ffx+8)
end if
if saf>0 then 
    BrowserType = "Safari"
    BrVerPlass = instr(ua,"version")
    BrVer = mid(ua,BrVerPlass+8,(instr(BrVerPlass,ua," ")-(BrVerPlass+8)))
end if
if crm>0 then 
    BrowserType = "Chrome"
    BrVer = mid(ua,crm+7,(instr(crm,ua," ")-(crm+7)))
end if
if max>0 then 
    BrowserType = "Maxthon"
    BrVer = mid(ua,max+8,(instr(max,ua," ")-(max+8)))
end if
if opr>0 then 
    BrowserType = "Opera"
    BrVerPlass = instr(ua,"presto")
    BrVer = mid(ua,BrVerPlass+7,(instr(BrVerPlass,ua," ")-(BrVerPlass+7)))
end if
if ie4>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "4"
end if
if ie5>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "5"
end if
if ie6>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "6"
end if
if ie7>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "7"
end if
if ie8>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "8"
    if ie7>0 then BrVer = BrVer & " (in IE7 compability mode)"
end if
if ie9>0 then 
    BrowserType = "Internet Explorer"
    BrVer = "9"
    if ie7>0 then BrVer = BrVer & " (in IE7 compability mode)"
    if ie8>0 then BrVer = BrVer & " (in IE8 compability mode)"
end if

OSSel = mid(ua,instr(ua,"(")+1,(instr(ua,";")-instr(ua,"("))-1)
OSver = mid(ua,instr(ua,";")+1,(instr(ua,")")-instr(ua,";"))-1)

if BrowserType = "Internet Explorer" then
    OSStart = instr(ua,";")
    OSStart = instr(OSStart+1,ua,";")        
    OSStopp = instr(OSStart+1,ua,";")
    OSsel = mid(ua,OSStart+2,(OSStopp-OSStart)-2)
end if

    Select case OSsel
        case "windows nt 6.1"
            OS = "Windows"
            OSver = "7"
        case "windows nt 6.0"
            OS = "Windows"
            OSver = "Vista"
        case "windows nt 5.2"
            OS = "Windows"
            OSver = "Srv 2003 / XP x64"
        case "windows nt 5.1"
            OS = "Windows"
            OSver = "XP"
        case else
            OS = OSSel
    End select

Response.write "<br>" & ua & "<br>" & BrowserType & "<br>" & BrVer & "<br>" & OS & "<br>" & OSver & "<br>"

'Use the variables here for whatever you need........

浏览器JavaScript库提供了此功能。

if (bowser.msie && bowser.version <= 6) {
  alert('Hello China');
}

它似乎保养得很好。

我根据Hermann Ingjaldsson的回答写了一个版本检测器，但是更健壮，它返回一个包含名称/版本数据的对象。它涵盖了主要的浏览器，但我不介意过多的移动浏览器和小浏览器:

function getBrowserData(nav) {
    var data = {};

    var ua = data.uaString = nav.userAgent;
    var browserMatch = ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*([\d\.]+)/i) || [];
    if (browserMatch[1]) { browserMatch[1] = browserMatch[1].toLowerCase(); }
    var operaMatch = browserMatch[1] === 'chrome';
    if (operaMatch) { operaMatch = ua.match(/\bOPR\/([\d\.]+)/); }

    if (/trident/i.test(browserMatch[1])) {
        var msieMatch = /\brv[ :]+([\d\.]+)/g.exec(ua) || [];
        data.name = 'msie';
        data.version = msieMatch[1];
    }
    else if (operaMatch) {
        data.name = 'opera';
        data.version = operaMatch[1];
    }
    else if (browserMatch[1] === 'safari') {
        var safariVersionMatch = ua.match(/version\/([\d\.]+)/i);
        data.name = 'safari';
        data.version = safariVersionMatch[1];
    }
    else {
        data.name = browserMatch[1];
        data.version = browserMatch[2];
    }

    var versionParts = [];
    if (data.version) {
        var versionPartsMatch = data.version.match(/(\d+)/g) || [];
        for (var i=0; i < versionPartsMatch.length; i++) {
            versionParts.push(versionPartsMatch[i]);
        }
        if (versionParts.length > 0) { data.majorVersion = versionParts[0]; }
    }
    data.name = data.name || '(unknown browser name)';
    data.version = {
        full: data.version || '(unknown full browser version)',
        parts: versionParts,
        major: versionParts.length > 0 ? versionParts[0] : '(unknown major browser version)'
    };

    return data;
};

它可以这样使用:

var brData = getBrowserData(window.navigator || navigator);
console.log('name: ' + brData.name);
console.log('major version: ' + brData.version.major);
// etc.

navigator.sayswho= (function(){ 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 'IE '+(tem[1] || ''); } if(M[1]=== 'Chrome'){ tem= ua.match(/\b(OPR|Edge)\/(\d+)/); if(tem!= null) return tem.slice(1).join(' ').replace('OPR', 'Opera'); } 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 M.join(' '); })(); console.log(navigator.sayswho); // outputs: `Chrome 62`