Detecting if IE7 or lower with conditional comments and javascript not working

Question

I'm trying to check if a person is using anything IE with version less than 8 or anything else.

I use conditional comments to declare boolean..

<!--[if lt IE 8]>
<script type="text/javascript">var badIE = true;</script>
<![endif]-->

And now I check in my js file the boolean like this:

if (badIE == true){
    alert('You have bad IE!');
} else {
    alert('Bueno!');
}

If I use IE7 or IE6, it alerts that "You have bad IE!". If I use anything else, it should alert "Bueno!", but it does not. What is the problem?

Answer 1

You need to declare the badIE variable as false first in order for it to work, or else the code outside of the conditional knows nothing about badIE

Try this:

<script>
    var badIE = false;
</script>

<!--[if lt IE 8]>
<script type="text/javascript">badIE = true;</script>
<![endif]-->

<script>
if (badIE == true){
    alert('You have bad IE!');
} else {
    alert('Bueno!');
}
</script>