jQuery第n次/每3次

我有一些如下的标记：

<h3>Mgmt</h3>   
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<h3>People</h3>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>

$(".ManagementOperations").each(function(index) {
    if ((index+1) % 3 == 0) $(this).addClass('rowEnd');
});

尝试：

尝试：

---

：nth子选择器将查找作为其父元素的第n个子元素的每个元素。似乎所有元素（包括H3）都具有相同的父元素，因此它只适用于您给定的每三个元素，例如第二个div。您可以将每个div集合包装到另一个div中，以将父元素的子元素约束到这些div。或者你可以这样做：

<h3>Mgmt</h3>   
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<h3>People</h3>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>

$(".ManagementOperations").each(function(index) {
    if ((index+1) % 3 == 0) $(this).addClass('rowEnd');
});

---

无论如何，类似的东西，我还没有测试过。

第n个子选择器将找到作为其父元素第n个子元素的每个元素。似乎所有元素（包括H3）都具有相同的父元素，因此它只适用于您给定的每三个元素，例如第二个div。您可以将每个div集合包装到另一个div中，以将父元素的子元素约束到这些div。或者你可以这样做：

<h3>Mgmt</h3>   
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<div class="ManagementOperations">bla bla </div>
<h3>People</h3>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>
<div class="people">bla bla </div>

$(".ManagementOperations").each(function(index) {
    if ((index+1) % 3 == 0) $(this).addClass('rowEnd');
});

不管怎么说，我还没有测试过