js判断ie方法集锦（含正则）代码短小经典 原创

是否是Opera:
<script> is_opera = /opera/i.test(navigator.userAgent); alert(is_opera); </script>
[Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]
是否是IE：
<script> is_opera = /opera/i.test(navigator.userAgent); var is_ie = (/msie/i.test(navigator.userAgent) && !is_opera) alert(is_ie); </script>
[Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]
是否是ie7：
代码如下:

<script> 
(is_ie && /msie 7\.0/i.test(navigator.userAgent));  
</script> 
 
 
<script> 
var isIe = /msie/i.test(navigator.userAgent); 
alert(isIe); 
</script> 

  [Ctrl+A 全选 注:如需引入外部Js需刷新才能执行] 
 
<script> 
   if(document.uniqueID){ 
         alert("脚本在IE浏览器中运行！"); 
     }else{ 
         alert("脚本在非IE浏览器中运行！"); 
     } 
</script> 

  [Ctrl+A 全选 注:如需引入外部Js需刷新才能执行] 

javascript判断ie版本 
 
<script> 
function Browser() { 
   var ua, s, i; 

   this.isIE     = false;   // Internet Explorer 
   this.isNS     = false;   // Netscape 
   this.version = null; 

   ua = navigator.userAgent; 

   s = "MSIE"; 
   if ((i = ua.indexOf(s)) >= 0) { 
     this.isIE = true; 
     this.version = parseFloat(ua.substr(i + s.length)); 
     return; 
   } 

   s = "Netscape6/"; 
   if ((i = ua.indexOf(s)) >= 0) { 
     this.isNS = true; 
     this.version = parseFloat(ua.substr(i + s.length)); 
     return; 
   } 

   // Treat any other "Gecko" browser as NS 6.1. 

   s = "Gecko"; 
   if ((i = ua.indexOf(s)) >= 0) { 
     this.isNS = true; 
     this.version = 6.1; 
     return; 
   } 
} 

var browser = new Browser();  
alert(browser); 
</script> 

  [Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]