css: does every class support :hover state?

If I use a class for a normal div, can I write the css like:

.messagebc开发者_C百科:hover {
...
}

Is it legal?

---

It's ineffiecient to use :hover on non-link elements.

Avoid the :hover pseudo-selector for non-link elements for IE clients.

If you use :hover on non-anchor elements, test the page in IE7 and IE8 to be sure your page is usable. If you find that :hover is causing performance issues, consider conditionally using a JavaScript onmouseover event handler for IE clients.

:hover pseudo-selector to non-link elements is a very ineffiecient selector (e.g): For example:

h3:hover {...}
.foo:hover {...}
#foo:hover {...}
div.faa :hover {...}

The :hover pseudo-selector on non-anchor elements is known to make IE7 and IE8 slow in some cases*. When a strict doctype is not used, IE7 and IE8 will ignore :hover on any element other than anchors. When a strict doctype is used, :hover on non-anchors may cause performance degradation.

More info on un-effiecient selectors

---

why havn't you simply tried it? yes, you can (in all modern browsers, the IE6 knows :hover only on a, if i remember right).

---

Yes you can use :hover for all elements in modern browsers (IE7+). While IE6 support :hover only for <a> elements, you should write you html and css so, that you won't need to use js-patches (for example, in list-menus just use <li><a href="#">Link</a></li>, not <a><li><a> and assign :hover to the link element. This should do the trick.)

---

Yes, however in IE6 you can set :hover only on ANCHOR elements.

---

Only ie6 does not support it on elements other than <a>, but that can be fixed with a simple javascript: ie7.js

---

The share of the ie6 is 5.55% and is decreasing everyday So You may use it Wikipedia ie6

---

Every current browser will support it. If you need it to work in an older browser such as IE6 then take a look at @Willem's link.

---

If by the term class you mean HTML element then yes per W3C spec you can use the :hover selector on all elements. Whether you should or not is a different question.

Sources:

http://www.w3schools.com/cssref/sel_hover.asp http://www.w3.org/2009/cheatsheet/#search,%3Ahover