[JS] JavaScript Browser Detection @ 以我為中心的宇宙

The JavaScript Navigator object contains all information about the visitor's browser. We are going to look at two properties of the Navigator object:appName - holds the name of the browser
appVersion - holds, among other things, the version of the browser

The variable browser in the example above holds the name of the browser, i.e. "Netscape" or "Microsoft Internet Explorer".

<html><body>
<script type="text/javascript">
var browser=navigator.appName;
var b_version=navigator.appVersion;
var version=parseFloat(b_version);document.write("Browser name: "+ browser);
document.write("<br />");
document.write("Browser version: "+ version);
</script>
</body></html>

The script below displays a different alert, depending on the visitor's browser:

<html>
<head>
<script type="text/javascript">
function detectBrowser(){var browser=navigator.appName;
var b_version=navigator.appVersion;
var version=parseFloat(b_version);
if ((browser=="Netscape"||browser=="Microsoft Internet Explorer")
&& (version>=4)){
alert("Your browser is good enough!");
}
else
{
alert("It's time to upgrade your browser!");
}}
</script>
</head><body onload="detectBrowser()">
</body>
</html>