无法在具有相同类名的多个类上应用 jQuery 代码？

Question

我在将 jQuery 代码应用于页面上具有相同类名的多个类时遇到一些问题。看起来该代码仅适用于其中一个类，但不适用于多个类。

如您所见，页面上有两个

TwoColumnUnit

类，但只有第一个

TwoColumnUnit

获取了 jQuery 代码，但没有获取第二个

TwoColumnUnit

类。

如何修复代码，以便该代码适用于具有相同类名的多个类？

$('.TwoColumnUnit').each(function() {
  var pairs = [document.querySelector('.TwoColumnUnit_Left'), document.querySelector('.TwoColumnUnit_Right')];
  pairs.forEach(function(pair) {
    if (pair) {
      var boxes = pair.getElementsByClassName('col-sm-12 col-md-6');
      var maxHeight = 0;
      Array.from(boxes).forEach(function(box) {
        box.style.height = ''; // Reset
        maxHeight = Math.max(maxHeight, box.offsetHeight);
      });
      Array.from(boxes).forEach(function(box) {
        box.style.height = maxHeight + 'px';
      });
    }
  });
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
<div class="TwoColumnUnit">
  <div class="col-md-6 col-xs-12 TwoColumnUnit_Left">
    <div class="newsLetterDiv">
      <div class="col-sm-12 col-md-6">
        <div class="left_Side">
          <i class="fas fas fa-route"></i>
          <h3>This is about Tennis</h3>
        </div>
        <div class="right_Side">
          <p><span>Tennis is a racket sport that is played either individually against a single opponent or between two teams of two players each.&nbsp;</span></p>
        </div>
      </div>
    </div>
    <div class="newsLetterDiv">
      <div class="col-sm-12 col-md-6">
        <div class="left_Side">
          <i class="fas fas fa-basketball"></i>
          <h3>This is about Basketball</h3>
        </div>
        <div class="right_Side">
          <p><span>Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.</span></p>
        </div>
      </div>
    </div>
  </div>
  <div class="col-md-6 col-xs-12 TwoColumnUnit_Right">
    <div class="newsLetterDiv">
      <div class="col-sm-12 col-md-6">
        <div class="left_Side">
          <i class="fas fas fa-basketball"></i>
          <h3>This is about Basketball</h3>
        </div>
        <div class="right_Side">
          <p><span>Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.</span></p>
        </div>
      </div>
    </div>
    <div class="newsLetterDiv">
      <div class="col-sm-12 col-md-6">
        <div class="left_Side">
          <i class="fas fas fa-route"></i>
          <h3>This is about Tennis</h3>
        </div>
        <div class="right_Side">
          <p><span>Tennis is a racket sport that is played either individually against a single opponent or between two teams of two players each.&nbsp;</span></p>
        </div>
      </div>
    </div>
  </div>
</div>



<div class="TwoColumnUnit">
  <div class="col-md-6 col-xs-12 TwoColumnUnit_Left">
    <div class="newsLetterDiv">
      <div class="col-sm-12 col-md-6">
        <div class="left_Side">
          <i class="fas fas fa-route"></i>
          <h3>This is about Tennis</h3>
        </div>
        <div class="right_Side">
          <p><span>Tennis is a racket sport that is played either individually against a single opponent or between two teams of two players each.&nbsp;</span></p>
        </div>
      </div>
    </div>
    <div class="newsLetterDiv">
      <div class="col-sm-12 col-md-6">
        <div class="left_Side">
          <i class="fas fas fa-basketball"></i>
          <h3>This is about Basketball</h3>
        </div>
        <div class="right_Side">
          <p><span>Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.</span></p>
        </div>
      </div>
    </div>
  </div>
  <div class="col-md-6 col-xs-12 TwoColumnUnit_Right">
    <div class="newsLetterDiv">
      <div class="col-sm-12 col-md-6">
        <div class="left_Side">
          <i class="fas fas fa-basketball"></i>
          <h3>This is about Basketball</h3>
        </div>
        <div class="right_Side">
          <p><span>Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.</span></p>
        </div>
      </div>
    </div>
    <div class="newsLetterDiv">
      <div class="col-sm-12 col-md-6">
        <div class="left_Side">
          <i class="fas fas fa-route"></i>
          <h3>This is about Tennis</h3>
        </div>
        <div class="right_Side">
          <p><span>Tennis is a racket sport that is played either individually against a single opponent or between two teams of two players each.&nbsp;</span></p>
        </div>
      </div>
    </div>
  </div>
</div>

Answer 1

querySelector()

只会选择

.TwoColumnUnit

中的第一次出现。您应该使用

querySelectorAll()

来代替。

另外，我建议你避免混合使用 JS 和 jQuery。

演示：

$('.TwoColumnUnit').each(function () {
    var pairs = [$(this).find('.TwoColumnUnit_Left'), $(this).find('.TwoColumnUnit_Right')];
    pairs.forEach(function (pair) {
        if (pair.length > 0) {
            var boxes = pair.find('.col-sm-12.col-md-6');
            var maxHeight = 0;
            boxes.each(function () {
                $(this).css('height', ''); // Reset
                maxHeight = Math.max(maxHeight, $(this).height());
            });
            boxes.css('height', maxHeight + 'px');
        }
    });
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div class="TwoColumnUnit">
    <div class="col-md-6 col-xs-12 TwoColumnUnit_Left">
        <div class="newsLetterDiv">
            <div class="col-sm-12 col-md-6">
                <div class="left_Side">
                    <i class="fas fas fa-route"></i>
                    <h3>This is about Tennis</h3>
                </div>
                <div class="right_Side">
                    <p><span>Tennis is a racket sport that is played either individually against a single opponent or between two teams of two players each.&nbsp;</span></p>
                </div>
            </div>
        </div>
        <div class="newsLetterDiv">
            <div class="col-sm-12 col-md-6">
                <div class="left_Side">
                    <i class="fas fas fa-basketball"></i>
                    <h3>This is about Basketball</h3>
                </div>
                <div class="right_Side">
                    <p><span>Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.</span></p>
                </div>
            </div>
        </div>
    </div>
    <div class="col-md-6 col-xs-12 TwoColumnUnit_Right">    
        <div class="newsLetterDiv">
            <div class="col-sm-12 col-md-6">
                <div class="left_Side">
                    <i class="fas fas fa-basketball"></i>
                    <h3>This is about Basketball</h3>
                </div>
                <div class="right_Side">
                    <p><span>Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.</span></p>
                </div>
            </div>
        </div>
        <div class="newsLetterDiv">
            <div class="col-sm-12 col-md-6">
                <div class="left_Side">
                    <i class="fas fas fa-route"></i>
                    <h3>This is about Tennis</h3>
                </div>
                <div class="right_Side">
                    <p><span>Tennis is a racket sport that is played either individually against a single opponent or between two teams of two players each.&nbsp;</span></p>
                </div>
            </div>
        </div>
    </div>
</div>



<div class="TwoColumnUnit">
    <div class="col-md-6 col-xs-12 TwoColumnUnit_Left">
        <div class="newsLetterDiv">
            <div class="col-sm-12 col-md-6">
                <div class="left_Side">
                    <i class="fas fas fa-route"></i>
                    <h3>This is about Tennis</h3>
                </div>
                <div class="right_Side">
                    <p><span>Tennis is a racket sport that is played either individually against a single opponent or between two teams of two players each.&nbsp;</span></p>
                </div>
            </div>
        </div>
        <div class="newsLetterDiv">
            <div class="col-sm-12 col-md-6">
                <div class="left_Side">
                    <i class="fas fas fa-basketball"></i>
                    <h3>This is about Basketball</h3>
                </div>
                <div class="right_Side">
                    <p><span>Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.</span></p>
                </div>
            </div>
        </div>
    </div>
    <div class="col-md-6 col-xs-12 TwoColumnUnit_Right">    
        <div class="newsLetterDiv">
            <div class="col-sm-12 col-md-6">
                <div class="left_Side">
                    <i class="fas fas fa-basketball"></i>
                    <h3>This is about Basketball</h3>
                </div>
                <div class="right_Side">
                    <p><span>Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop, while preventing the opposing team from shooting through their own hoop.</span></p>
                </div>
            </div>
        </div>
        <div class="newsLetterDiv">
            <div class="col-sm-12 col-md-6">
                <div class="left_Side">
                    <i class="fas fas fa-route"></i>
                    <h3>This is about Tennis</h3>
                </div>
                <div class="right_Side">
                    <p><span>Tennis is a racket sport that is played either individually against a single opponent or between two teams of two players each.&nbsp;</span></p>
                </div>
            </div>
        </div>
    </div>
</div>