如何判斷頁面是在移動端還是PC端打開的呢

1.   window.location.href = /Android|webOS|iPhone|iPod|BlackBerry/i.test(navigator.userAgent) ? "https://www.baidu.com/" :  "http://news.baidu.com/";

2.

if(/Android|webOS|iPhone|iPod|BlackBerry/i.test(navigator.userAgent)) {
    window.location.href = "https://www.baidu.com/";
} else {
    window.location.href = "http://news.baidu.com/";
}

判斷是否微信瀏覽器打開

function is_weixn(){
　　var ua = navigator.userAgent.toLowerCase();
　　if(ua.match(/MicroMessenger/i)=="micromessenger") {
　　　　return true;
　　} else {
　　　　return false;
　　}
}

<script type="text/javascript">
        function browserRedirect() {
            var sUserAgent = navigator.userAgent.toLowerCase();
            var bIsIpad = sUserAgent.match(/ipad/i) == "ipad";
            var bIsIphoneOs = sUserAgent.match(/iphone os/i) == "iphone os";
            var bIsMidp = sUserAgent.match(/midp/i) == "midp";
            var bIsUc7 = sUserAgent.match(/rv:1.2.3.4/i) == "rv:1.2.3.4";
            var bIsUc = sUserAgent.match(/ucweb/i) == "ucweb";
            var bIsAndroid = sUserAgent.match(/android/i) == "android";
            var bIsCE = sUserAgent.match(/windows ce/i) == "windows ce";
            var bIsWM = sUserAgent.match(/windows mobile/i) == "windows mobile";
            document.writeln("您的瀏覽設備為：");
            if (bIsIpad || bIsIphoneOs || bIsMidp || bIsUc7 || bIsUc || bIsAndroid || bIsCE || bIsWM) {
                document.writeln("phone");
            } else {
                document.writeln("pc");
            }
        }

        browserRedirect();
</script>
-------------------

<script type="text/javascript"> //判斷訪問終端 var browser={ versions:function(){ var u = navigator.userAgent, app = navigator.appVersion; return { trident: u.indexOf('Trident') > -1, //IE內核 presto: u.indexOf('Presto') > -1, //opera內核 webKit: u.indexOf('AppleWebKit') > -1, //蘋果、谷歌內核 gecko: u.indexOf('Gecko') > -1 && u.indexOf('KHTML') == -1,//火狐內核 mobile: !!u.match(/AppleWebKit.*Mobile.*/), //是否為移動終端 ios: !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/), //ios終端 android: u.indexOf('Android') > -1 || u.indexOf('Linux') > -1, //android終端或者uc瀏覽器 iPhone: u.indexOf('iPhone') > -1 , //是否為iPhone或者QQHD瀏覽器 iPad: u.indexOf('iPad') > -1, //是否iPad webApp: u.indexOf('Safari') == -1 //是否web應該程序，沒有頭部與底部 }; }(), language:(navigator.browserLanguage || navigator.language).toLowerCase();//檢測瀏覽器語言 } //browser.versions.trident返回真假，真則是IE內核，以此類推browser.versions.webKit是否為谷歌內核 //判斷是否IE內核 if(browser.versions.trident){ alert("is IE"); } //判斷是否webKit內核 if(browser.versions.webKit){ alert("is webKit"); } //判斷是否移動端 if(browser.versions.mobile||browser.versions.android||browser.versions.ios){ alert("移動端"); } </script>