IE条件语句 IE hack大全

<!--[if IE 6]>Special instructions for IE 6 here<![endif]-->
[code]

Their basic structure is the same as an HTML comment (<!-- -->). Therefore all other browsers will see them as normal comments and will ignore them entirely.
IE, though, has been programmed to recognize the special <!--[if IE]> syntax, resolves the ifand parses the content of the conditional comment as if it were normal page content.
Since conditional comments use the HTML comment structure, they can only be included in HTML files, and not in CSS files. I'd have preferred to put the special styles in the CSS file, but that's impossible. You can also put an entire new <link> tag in the conditional comment referring to an extra style sheet.
Example
Below I added a lot of conditional comments that print out messages according to your IE version.

Note however, that if you use multiple Explorers on one computer, the conditional comments will render as if all these Explorer versions are the highest Explorer version available on your machine (usually Explorer 6.0).

Test
Below are a few conditional comments that reveal the IE version you're using.

According to the conditional comment this is IE
According to the conditional comment this is IE 7
According to the conditional comment this is IE lower than 9
According to the conditional comment this is IE lower or equal to 7
According to the conditional comment this is IE greater than 6

Code
The syntax I use is:
[code]
<p class="accent">
<!--[if IE]>
According to the conditional comment this is IE<br />
<![endif]-->
<!--[if IE 6]>
According to the conditional comment this is IE 6<br />
<![endif]-->
<!--[if IE 7]>
According to the conditional comment this is IE 7<br />
<![endif]-->
<!--[if IE 8]>
According to the conditional comment this is IE 8<br />
<![endif]-->
<!--[if IE 9]>
According to the conditional comment this is IE 9<br />
<![endif]-->
<!--[if gte IE 8]>
According to the conditional comment this is IE 8 or higher<br />
<![endif]-->
<!--[if lt IE 9]>
According to the conditional comment this is IE lower than 9<br />
<![endif]-->
<!--[if lte IE 7]>
According to the conditional comment this is IE lower or equal to 7<br />
<![endif]-->
<!--[if gt IE 6]>
According to the conditional comment this is IE greater than 6<br />
<![endif]-->
<!--[if !IE]> -->
According to the conditional comment this is not IE<br />
<!-- <![endif]-->
</p>