javascript - 为什么不触发不同版本的IE

Question

我有以下脚本来检查我正在运行的 IE 版本并使用样式表并显示警报语句:

var div = document.createElement("div");
        div.innerHTML = "<!--[if lte IE 9]><i></i><![endif]-->";
        var isIeLessThan9 = (div.getElementsByTagName("i").length == 1);
        if (isIeLessThan9) {
            alert("<=9");
            document.write('<link rel="stylesheet" href="theStyles/defaultStyle_ie.css" type="text/css" charset="utf-8" />');
            document.write('<link rel="stylesheet" href="theStyles/captionStyle_ie.css" type="text/css" charset="utf-8" />');
        }
        if (!isIeLessThan9) {
            alert(">9");
            document.write('<link rel="stylesheet" href="theStyles/defaultStyle.css" type="text/css" charset="utf-8" />');
            document.write('<link rel="stylesheet" href="theStyles/captionStyle.css" type="text/css" charset="utf-8" />');
        }

对于 IE 版本 10 和更高版本，它显示 >=10 并且低于 IE 版本 10 的任何内容仍然显示 >=10

我该如何解决？

编辑:

这是应该可以解决问题的更新代码:

<script  type="text/javascript">
    var isMobile = {
        Android: function () {
            return navigator.userAgent.match(/Android/i);
        },
        BlackBerry: function () {
            return navigator.userAgent.match(/BlackBerry/i);
        },
        iOS: function () {
            return navigator.userAgent.match(/iPhone|iPad|iPod/i);
        },
        Opera: function () {
            return navigator.userAgent.match(/Opera Mini/i);
        },
        Windows: function () {
            return navigator.userAgent.match(/IEMobile/i);
        },
        any: function () {
            return (isMobile.Android() || isMobile.BlackBerry() || isMobile.iOS() || isMobile.Opera() || isMobile.Windows());
        }
    };



    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+(\.\d+)?)/g.exec(ua) || [];
        return 'IE '+(tem[1] || '');
    }
    M= M[2]? [M[1], M[2]]:[navigator.appName, navigator.appVersion, '-?'];
    if((tem= ua.match(/version\/([\.\d]+)/i))!= null) M[2]= tem[1];
    return M.join(' ');
})();
var browserversion1 = navigator.sayswho.split(" ");
var browserversion2 = browserversion1[1].split(".")[0].split(",");
var isIeLessThan10 = browserversion1[0] == "IE" && browserversion2[0] < 10;




    if (!isMobile.any()) {
        if (isIeLessThan10) {
            alert("IE<10");
            document.write('<link rel="stylesheet" href="theStyles/defaultStyle_ie.css" type="text/css" charset="utf-8" />');
            document.write('<link rel="stylesheet" href="theStyles/captionStyle_ie.css" type="text/css" charset="utf-8" />');
        }
        else {
            alert("IE>=10 || !IE");
            document.write('<link rel="stylesheet" href="theStyles/defaultStyle.css" type="text/css" charset="utf-8" />');
            document.write('<link rel="stylesheet" href="theStyles/captionStyle.css" type="text/css" charset="utf-8" />');
        }
    }
    else {
        alert("mobile");
        document.write('<link rel="stylesheet" href="theStyles/defaultStyle_mobile.css" type="text/css" charset="utf-8" />');
        document.write('<link rel="stylesheet" href="theStyles/captionStyle_mobile.css" type="text/css" charset="utf-8" />');
    }
</script>

IE8 和 FF 都显示警告，IE>=10 || !IE

Answer 1

我宁愿使用这个函数来获取浏览器及其版本，而不是依赖 html 标签计数，这可以很容易地随着您的内容而改变:JSFiddle

 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+(\.\d+)?)/g.exec(ua) || [];
        return 'IE '+(tem[1] || '');
    }
    M= M[2]? [M[1], M[2]]:[navigator.appName, navigator.appVersion, '-?'];
    if((tem= ua.match(/version\/([\.\d]+)/i))!= null) M[2]= tem[1];
    return M.join(' ');
})();
var browserversion1 = navigator.sayswho.split(" ");
var browserversion2 = browserversion1[1].split(".")[0].split(",");
var isIeLessThan10 = (browserversion1[0] == "IE" || browserversion1[0] == "MSIE") && browserversion2[0] < 10;