<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>navigator对象及属性(userAgent)(扩展)</title>
<!--
Navigator 对象包含有关浏览器的信息
navigator.userAgent;用户使用的系统信息及浏览器信息
-->
</head>
<body>
<script>
var browse,nav=navigator.userAgent;
console.log(nav);
function na(){
var browse,explorer=navigator.userAgent.toLowerCase();//获取浏览器信息并将其变成小写
if (explorer.indexOf("trident")>-1){ //indexOf如果找到ie会返回ie的索引值,如果找不到会返回-1,
browse="IE";
}else if(explorer.indexOf("chrome")>-1){
browse="chrome";
}else if(explorer.indexOf("opera")>-1){
browse="opera";
}else if(explorer.indexOf("safari")>-1){
browse="safari";
}
return browse;
}
var bro=na();
alert("当前为:"+bro+"浏览器");
</script>
</body>
</html>