javascript - JQuery running contains on this variable/object

Question

好吧，我对此很迷茫。首先，我使用 $this 获得对 jquery li 对象的引用，然后我尝试使用“包含”jquery 函数在该 li 中搜索是否存在某些文本。但是带有“包含”的行永远不会返回 true。

$("ul li").each(function(index) {
  var $this = $(this);

  //Attempt 1 using $this
  if ($this.is(":contains('some text' ) ")) {
    console.log("	matching free text found");
  } else {
    console.log("	matching free text not found");
  }
  //Attempt 2 using $(this)
  if ($(this).is(":contains('some text' ) ")) {
    console.log("	matching free text found");
  } else {
    console.log("	matching free text not found");
  }


})

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

<ul>
  <li>one</li>
  <li>two</li>
  <li>some text here</li>
</ul>

Answer 1

您只需从 :contains(some text) 中删除 ' '。

jQuery 文档: jQuery - contains selector

$("ul li").each(function(index) {
  var $this = $(this);

  //Attempt 1 using $this
  if ($this.is(":contains(some text) ")) {
    console.log("	matching free text found at Index: " + index);
  } else {
    console.log("	matching free text not found");
  }
  //Attempt 2 using $(this)
  if ($(this).is(":contains(some text ) ")) {
    console.log("	matching free text found at index: " + index);
  } else {
    console.log("	matching free text not found");
  }
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<ul>
  <li>one</li>
  <li>two</li>
  <li>some text here</li>
</ul>