javascript - Detect whether browser is IE 7 or lower?

Question

So i am going to add a redirect to my site to toss every one that is using ie 7 or lower off to a different page and came up with this JavaScript, but it seems to have stopped working.

<script type="text/javascript">
 if (/MSIE (d+.d+);/.test(navigator.userAgent)){ //test for MSIE x.x;
  var ieversion=new Number(RegExp.$1) // capture x.x portion and store as a number
   if (ieversion<=8)
    window.location = "ie.html" 
   }
   window.location = "main.html"
</script>

Answer 1

Your code is always resulting to having gone to main.html. Even when the code falls into <8, you'll fall out of the if into setting to main.

Consider refactoring by either:

• setting a return after setting to ie.

or

var redir="main.html";
if (/MSIE (d+.d+);/.test(navigator.userAgent))
{ 
   var ieversion=new Number(RegExp.$1);
   if (ieversion<=8)
   {
      redir = "ie.html";
   }
}
window.location = redir;