How can I get IE8 to accept a CSS :before tag?

问题:

I have the following CSS code

.editable:before {
    content: url(../images/icons/icon1.png);
    padding-right:5px;
}

this is used in conjunction with the following markup:

<span class="editable"></span>

In every other blessed browser in the world my icon is appearing, but IE8 seems to have a problem with this. Isn't the :before pseudo-element CSS2? isn't content: also a CSS2 command? what gives?

回答1:

Update: I misread the page! IE 8 does support :before with images, it just doesn't when it is in IE7 compatibility mode.

IE8 supports :before, but not and also images as content when not in compatibility mode. Kudos to @toscho for testing!

• Source

• Detailed comparison of which browsers can deal with what sort of content

How I love quirksmode.org, which makes dealing with this stuff at least half-way bearable. The guy deserves a medal!

回答2:

Actually you should be careful here and read the detail. For full details, see this link - which states

In Windows Internet Explorer 8, as well as later versions of Windows Internet Explorer in IE8 Standards mode, only the one-colon form of this pseudo-element is recognized—that is, :before. Beginning with Windows Internet Explorer 9, the ::before pseudo-element requires two colons, though the one-colon form is still recognized and behaves identically to the two-colon form.

Meaning for browsers <IE9 - you must use :before and for >=IE9 - you must use ::before

回答3:

When using :before and :after, just be careful not to use double colons (::after - will not work, but :after will work). I lost about 20mins for this...