IE8 javascript被检测为IE7

Question

I trying to detect ie 7 or 6 and redirect users to the error page using the javascript bellow

 var Browser = {
        Version: function () {
            var version = 999; // we assume a sane browser
            if (navigator.appVersion.indexOf("MSIE") != -1)
            // bah, IE again, lets downgrade version number
                version = parseFloat(navigator.appVersion.split("MSIE")[1]);
            return version;
        }
    }

    if (Browser.Version() == 7 || Browser.Version() == 6) {

        if (window.location.href != "/browser_problem") {
            window.location.href = "/browser_problem";
        }
    }

I got some Feedback, that ie version 8.0.7601.17514 is redirect users to the error page like they are on ie 7 or 6.

Any idea what can be the problem?

Answer 1

I assume that you got this solution from here ?

If you read through the comments for the chunk of code you're using (on the link above) you'll see that someone else had the same issue you're having.

The code itself is sound (although you'll find a few people who don't feel that browser-sniffing in this fashion is good practice).

The reason Internet Explorer 8 is getting caught and redirected is either:

• The user has their browser in IE7 compatibility mode (which is possible from the Tools menu, or the little browser icon in the URL bar - IE8 was intended to be intelligent enough to detect and switched to IE7 mode automatically. This is usually caused by invalid markup);
• The website itself is forcing their browser into IE7-mode using X-UA-Compatible or similar.

To get to the bottom of your issues, get hold of a copy of IE8 and try it out for yourself (you can use BrowserStack - a really good in-browser resource for cross-browser testing), if you can replicate it using IE8, make sure you're not in IE7 mode in the Tools menu.

Take a look at the HTML markup on your page and ensure that you don't have an X-UA-Compatible meta-tag that looks something like this in the head:

<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" />

Which could be changed to:

<meta http-equiv="X-UA-Compatible" content="IE=edge">