我想将属性更改为许多元素都具有相同的类。

我有很多带有“ data-lc-categories = all”属性的“ a”标签。

我想将该属性（data-lc-categories）更改为所有带有动画类别的a标签，使其变为data-lc-categories =“ animation”。

我的问题是，如果我尝试使用ID选择元素，则可以使用

setattribute('data-lc-categories','animation'); // javascript

OR

$('#test1').attr({
    "data-lc-categories": "animation","title": "some title"
}); // jQuery

但是当我尝试

document.getElementsByClassname(".img_portfolio_animation")
 .setattribute('data-lc-categories','animation');

OR

$('.animation').attr("data-lc-categories": "animation") 

它不起作用。

<div class="new_filter_btns_container">
    <ul>
         <li id="filter_All" class="filter_btn">All</li>
         <li id="filter_animations" class="filter_btn">Animations</li>
         <li id="filter_interior" class="filter_btn">Interior Renders</li>
    </ul>
</div>

<a id="test1" class="animation all" href="" data-rel="lightcase:myCollection" data-lc-categories="All">Animation</a>
<a class="animation all" href="" data-rel="lightcase:myCollection" data-lc-categories="All">Animation</a>
<a class="animation all" href="" data-rel="lightcase:myCollection" data-lc-categories="All">Animation</a>
<a class="animation all" href="" data-rel="lightcase:myCollection" data-lc-categories="All">Animation</a>
<a class="interior all" href="" data-rel="lightcase:myCollection" data-lc-categories="All">Interior</a>
<a class="interior all" href="" data-rel="lightcase:myCollection" data-lc-categories="All">Interior</a>
<a class="interior all"     href="" data-rel="lightcase:myCollection" data-lc-categories="All">Interior</a>
<a class="interior all" href="" data-rel="lightcase:myCollection" data-lc-categories="All">Interior</a>