Question

如何删除活动课程。下面是我的代码，首先我找到id标签然后是类，但是这段代码不起作用：

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function myFunction() {
  var element1 = document.getElementById('grid3d');
  var remove_class = 'active';

  element1.className = element1.className.replace(' ' + remove_class, '').replace(remove_class, '');
}

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.active {
  color: red;
}

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<div id="grid3d">Hello World

  <figure ">Click the button to remove the class attribute from the h1 element.</figure>
    
    <figure class="active ">Click the button to remove the class attribute from the h1 element.</figure>
    
    <figure>Click the button to remove the class attribute from the h1 element.</figure>
    </div>
    <button onclick="myFunction() ">Try it</button>

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Answer 1

试试这个代码段

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function myFunction() {
  var fig = document.querySelectorAll('figure');

  for (var i = 0; i < fig.length; i++) {
    if (fig[i].className == "active") {
      fig[i].className = "";
    }
  }

}

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.active {
  color: purple;  
}

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<div id="grid3d">Hello World

  <figure>Click the button to remove the class attribute from the h1 element.</figure>

  <figure class="active">Click the button to remove the class attribute from the h1 element.</figure>

  <figure>Click the button to remove the class attribute from the h1 element.</figure>
</div>
<button onclick="myFunction()">Try it</button>

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Answer 2

你可以尝试在图元素

上使用classList.remove（）函数

function myFunction() {
  var element1 = document.getElementById('grid3d'),
      remove_class = 'active',
      figureEl = element1.querySelector('.' + remove_class);


  figureEl.className.remove(remove_class);
}

我希望它能奏效。

Answer 3

如果我理解正确，您想删除第二个<figure>的ID。您可以使用JS方法removeAttribute()。它使您可以从元素标记中删除任何属性。

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var removeClass = function(selector) {
  var el = document.querySelector(selector);
  el.removeAttribute('id');
}

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#active {
  color: red;
}

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<div>Remove #active! from the second figure tag

  <figure>Click the button to remove the class attribute from the h1 element.</figure>

  <figure id="active">Click the button to remove the class attribute from the h1 element.</figure>

  <figure>Click the button to remove the class attribute from the h1 element.</figure>
</div>
<button onclick="removeClass('#active')">Try it</button>

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如何在javascript中删除标记子类的类

3 个答案: