把元素集合筛选为包含指定文本（区分大小写）的元素。

返回值:jQuery

参数:

• str (String): 包含在元素中的文本

示例:

$("p").contains("test")

HTML 代码:

<p>This is just a test.</p><p>So is   this</p>

结果:

[ <p>This is just a test.</p> ] 

Filter the set of elements to those that contain the specified text.

Return value: jQuery
Parameters:

• str (String): The string that will be contained within the text of an element.

Example:

 $("p").contains("test")  

 <p>This is just a test.</p><p>So is this</p>  

 [ <p>This is just a test.</p> ]