CSS选择器“如果有这个孩子”

Question

I am trying to select this div:

<div class="k-widget k-window">

if it has this child

<div id="window_Monthly">

I've tried:

$("div.k-window:has(div#window_Monthly)")

Answer 1

You should avoid using :has() . According to API,

Because :has() is a jQuery extension and not part of the CSS specification, queries using :has() cannot take advantage of the performance boost provided by the native DOM querySelectorAll() method. For better performance in modern browsers, use $("your-pure-css-selector").has(selector/DOMElement) instead.

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However, there are a few other ways you can go about this:

SELECTORS:

$("div.k-window div#window_Monthly")
$(".k-window #window_Monthly")

DEMO: http://jsfiddle.net/JHQXd/1/

IF/LENGTH:

IMO, it would be best to use .find() instead of .children() but both are valid.

if($('div.k-window').find('#window_Monthly').length)
     //do something

or

if($('div.k-window').find('#window_Monthly').length > 0)
         //do something

DEMO: http://jsfiddle.net/JHQXd/2/

Answer 2

Your solution works. Please check this jsFiddle : http://jsfiddle.net/JHQXd/

Answer 3

$('.k-widget>#window_Monthly').parent()

如果孩子不是一级后代：

$('.k-widget #window_Monthly').parents('.k-widget')