返回值:jQuerychildren([selector])

Get the children of each element in the set of matched elements, optionally filtered by a selector.

Given a jQuery object that represents a set of DOM elements, the .children() method allows us to search through the immediate children of these elements in the DOM tree and construct a new jQuery object from the matching elements. The .find() and .children() methods are similar, except that the latter only travels a single level down the DOM tree. Note also that like most jQuery methods, .children() does not return text nodes; to get all children including text and comment nodes, use .contents().

The method optionally accepts a selector expression of the same type that we can pass to the $() function. If the selector is supplied, the elements will be filtered by testing whether they match it.

Consider a page with a basic nested list on it:

<ul class="level-1">
  <li class="item-i">I</li>
  <li class="item-ii">II
    <ul class="level-2">
      <li class="item-a">A</li>
      <li class="item-b">B
        <ul class="level-3">
          <li class="item-1">1</li>
          <li class="item-2">2</li>
          <li class="item-3">3</li>
        </ul>
      </li>
      <li class="item-c">C</li>
    </ul>
  </li>
  <li class="item-iii">III</li>
</ul>

If we begin at the level-2 list, we can find its children:

$('ul.level-2').children().css('background-color', 'red');

The result of this call is a red background behind items A, B, and C. Since we do not supply a selector expression, all of the children are part of the returned jQuery object. If we had supplied one, only the matching items among these three would be included.

示例:

Find all children of the clicked element.

<!DOCTYPE html>
<html>
<head>
<style>
  body { font-size:16px; font-weight:bolder; }
  div { width:130px; height:82px; margin:10px; float:left;
        border:1px solid blue; padding:4px; }
  #container { width:auto; height:105px; margin:0; float:none;
        border:none; }
  .hilite { border-color:red; }
  #results { display:block; color:red; }
  p { margin:10px; border:1px solid transparent; }
  span { color:blue; border:1px solid transparent; }
  input { width:100px; }
  em { border:1px solid transparent; }
  a { border:1px solid transparent; }
  b { border:1px solid transparent; }
  button { border:1px solid transparent; }
  </style>
<script src="jquery.min.js"></script>
</head>
<body>

<div id="container">

    <div>
      <p>This <span>is the <em>way</em> we</span> 
      write <em>the</em> demo,</p>

    </div>
    <div>
      <a href="#"><b>w</b>rit<b>e</b></a> the <span>demo,</span> <button>write 
      the</button> demo,
    </div>

    <div>
      This <span>the way we <em>write</em> the <em>demo</em> so</span>

      <input type="text" value="early" /> in
    </div>
    <p>
      <span>t</span>he <span>m</span>orning.
      <span id="results">Found <span>0</span> children in <span>TAG</span>.</span>

    </p>
  </div>

<script>



    $("#container").click(function (e) {
      $("*").removeClass("hilite");
      var $kids = $(e.target).children();
      var len = $kids.addClass("hilite").length;

      $("#results span:first").text(len);
      $("#results span:last").text(e.target.tagName);

      e.preventDefault();
      return false;
    });


</script>
</body>
</html>
演示:

示例:

Find all children of each div.

<!DOCTYPE html>
<html>
<head>
<style>
  body { font-size:16px; font-weight:bolder; }
  span { color:blue; }
  p { margin:5px 0; }
  </style>
<script src="jquery.min.js"></script>
</head>
<body>

<p>Hello (this is a paragraph)</p>

  <div><span>Hello Again (this span is a child of the a div)</span></div>
  <p>And <span>Again</span> (in another paragraph)</p>

  <div>And One Last <span>Time</span> (most text directly in a div)</div>

<script>

$("div").children().css("border-bottom", "3px double red");

</script>
</body>
</html>
演示:

示例:

Find all children with a class "selected" of each div.

<!DOCTYPE html>
<html>
<head>
<style>

  body { font-size:16px; font-weight:bolder; }
  p { margin:5px 0; }
  </style>
<script src="jquery.min.js"></script>
</head>
<body>

<div>
    <span>Hello</span>
    <p class="selected">Hello Again</p>
    <div class="selected">And Again</div>

    <p>And One Last Time</p>
  </div>

<script>

$("div").children(".selected").css("color", "blue");

</script>
</body>
</html>
演示: