javascript - 计算带Java的Div中有多少UL元素？(Count how many UL Elements there are in a Div with Javascript?)

Question

I am dynamically adding UL elements to a DIV element.

(我正在将UL元素动态添加到DIV元素。)

I would like to be able to count how many UL elements there are inside the DIV so that once all the ULs are removed dynamically I can delete the DIV that they are contained in.

(我希望能够计算DIV中有多少个UL元素，以便一旦动态删除所有UL，就可以删除其中包含的DIV。)

<div id="000">

<ul id="000-1">
<li>Stuff</li>
<li>Stuff</li>
</ul>

<ul id="000-2">
<li>Stuff</li>
<li>Stuff</li>
</ul>

</div>

Is there a simple Javascript solution that counts the amount of ULs so that I can do something like this.. ?

(是否有一个简单的Javascript解决方案可以计算UL的数量，以便我可以执行类似的操作。)

if(ulcount == 0){

var remove = document.getElementById("000");
remove.innerHTML = '';
results.parentNode.removeChild("000");

}

Thanks.

(谢谢。)

  ask by Wez translate from so

Answer 1

@Cheeso's answer is a good pure-JS solution.

(@Cheeso的答案是一个很好的纯JS解决方案。)

But, if you're using jQuery, the process can be made simpler.

(但是，如果您使用的是jQuery，则可以简化此过程。)

jQuery('div#000').children('ul').length;

The above code will return the number of child ul elements of the div#000 .

(上面的代码将返回div#000的子ul元素的数量。)

To update the count when you add elements dynamically, you will have to create a function and call it to update the number whenever a change occurs:

(要在动态添加元素时更新计数，您将必须创建一个函数并在发生更改时调用它以更新数字：)

function countUls() {jQuery('div#000').children('ul').length;}

Bind that to an event so that it will be called when you want to update the number.

(将该事件绑定到事件，以便在您要更新号码时将其调用。)