第一个选择器不会首先过滤，但第一个选择器会过滤

Question

I've used first many times but this time it doesn't work and no errors in console. I have this html:

<ul>
<li class="iheader"><h1>TITLE</h1></li>
//some more list items
<li class="iheader"></li> 
</ul>

Now running this code :

$('.iheader:first').removeClass('iheader');

Removes both classes. I've also tried :

$('.iheader').filter(':first').removeClass('iheader');

And same result.

However if i use first:child it does work when the html is as mentioned above.

anyone may know why? could this be related to the fact that i'm including jQuery mobile?

Answer 1

尝试

$('.iheader:first-child').removeClass('iheader');

Answer 2

首先使用jQuery ：

$('.iheader').first().removeClass('iheader');

Answer 3

对于那些想知道为什么cmes解决方案有效的人，是因为jQuery可以选择使用CSS选择器，而:first-child是一个css选择器，它为元素的css指定了css，它是其父元素的第一个子元素。