在只对行中的列应用解决方案1时，会出现一个问题。想改进解决方案1。

 [class^="col-"]:not([class*="-12"]){
      margin-bottom: -99999px;
      padding-bottom: 99999px;
  }

(抱歉，不能评论Popnoodles的回答。我的名声不够好)

最新解决方案(2022年)

解决方案4使用Bootstrap 4或5

Bootstrap 4和5默认使用Flexbox，因此不需要额外的CSS。

Demo

<div class="container">
    <div class="row ">
        <div class="col-md-4" style="background-color: red">
          some content
        </div>
        <div class="col-md-4" style="background-color: yellow">
          catz
          <img width="100" height="100" src="https://placekitten.com/100/100/">
        </div>
        <div class="col-md-4" style="background-color: green">
          some more content
        </div>
    </div>
</div>

解决方案1使用负边距(不会破坏响应性)

Demo

.row{
    overflow: hidden; 
}

[class*="col-"]{
    margin-bottom: -99999px;
    padding-bottom: 99999px;
}

解决方案2使用表

Demo

.row {
    display: table;
}

[class*="col-"] {
    float: none;
    display: table-cell;
    vertical-align: top;
}

使用flex的解决方案3于2015年8月添加。在此之前发布的评论不适用于此解决方案。

Demo

.row {
  display: -webkit-box;
  display: -webkit-flex;
  display: -ms-flexbox;
  display:         flex;
  flex-wrap: wrap;
}
.row > [class*='col-'] {
  display: flex;
  flex-direction: column;
}

我尝试了在这个帖子和其他页面上提出的很多建议，但没有一个解决方案在所有浏览器中都100%有效。

所以我做了很长时间的实验，得出了这个结论。 一个完整的解决方案，Bootstrap等高列与flexbox的帮助下，只有一个类。这适用于所有主流浏览器IE10+。

CSS:

.row.equal-cols {
  display: -webkit-flex;
  display: -ms-flexbox;
  display: flex;
  -webkit-flex-wrap: wrap;
  -ms-flex-wrap: wrap;
  flex-wrap: wrap;
}

.row.equal-cols:before,
.row.equal-cols:after {
  display: block;
}

.row.equal-cols > [class*='col-'] {
  display: -webkit-flex;
  display: -ms-flexbox;
  display: flex;
  -webkit-flex-direction: column;
  -ms-flex-direction: column;
  flex-direction: column;
}

.row.equal-cols > [class*='col-'] > * {
  -webkit-flex: 1 1 auto;
  -ms-flex: 1 1 auto;
  flex: 1 1 auto; 
}

HTML:

<div class="container">
  <div class="row equal-cols">
    <div class="col-sm-4">
      <div class="content"></div>
    </div>
    <div class="col-sm-4">
      <div class="content"></div>
    </div>
    <div class="col-sm-4">
      <div class="content"></div>
    </div>
  </div>
</div>

为了支持更多版本的IE，你可以，例如，使用https://github.com/liabru/jquery-match-height和目标。equal-cols的所有子列。是这样的:

// Create a check for IE9 (or any other specific browser).
if(IE9) {
  $(".row.equal-cols > [class*='col-']").matchHeight();
}

没有这个填充列将表现为通常引导列，所以这是一个相当好的退一步。

这是我的方法，我已经使用flex与一些变化的媒体查询。

  @media (min-width: 0px) and (max-width: 767px) {
  .fsi-row-xs-level {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
  }
}
@media (min-width: 768px) and (max-width: 991px) {
  .fsi-row-sm-level {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
  }
}
@media (min-width: 992px) and (max-width: 1199px) {
  .fsi-row-md-level {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
  }
}
@media (min-width: 1200px) {
  .fsi-row-lg-level {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
  }
}

然后将所需的类添加到父类中。

<div class="row fsi-row-lg-level fsi-row-md-level">
<div class="col-sm-4">column 1</div>
<div class="col-sm-4">column 2</div>
<div class="col-sm-4">column 3</div>
</div>

我使用响应式断点，因为流量通常会阻碍引导标准响应特性。

你也可以使用内联伸缩，这工作得很好，可能比用CSS修改每个行元素要干净一点。

对于我的项目，我希望每行谁的子元素有边界是相同的高度，这样边界将看起来参差不齐。为此，我创建了一个简单的css类。

.row.borders{
    display: inline-flex;
    width: 100%;
}

要回答你的问题，这是所有你需要看到完整的响应式演示与前缀css:

/* Using col-xs media query breakpoint but you can change 481 to 768 to only apply to col-sm and above if you'd like*/

@media only screen and (min-width : 481px) {
    .flex-row {
        display: flex;
        flex-wrap: wrap;
    }
    .flex-row > [class*='col-'] {
        display: flex;
        flex-direction: column;
    }
    .flex-row.row:after, 
    .flex-row.row:before {
        display: flex;
    }
}

要添加缩略图内容的支持，在伸缩列中，如上面的截图，还添加这个…注意，你也可以在面板上做到这一点:

.flex-row .thumbnail,
.flex-row .caption {
    display: flex;
    flex: 1 0 auto;
    flex-direction: column;
}
.flex-text {
    flex-grow: 1;
}    
.flex-row img {
    width: 100%;
}

虽然flexbox不能在IE9及以下版本中工作，但你可以使用带有条件标签的演示版本，并使用类似javascript网格的东西作为填充:

<!--[if lte IE 9]>

<![endif]-->

As for the other two examples in the accepted answer... The table demo is a decent idea but is being implemented wrong. Applying that CSS on bootstrap column classes specifically will without a doubt break the grid framework entirely. You should be using a custom selector for one and two the tables styles should not be applied to [class*='col-'] that have defined widths. This method should ONLY be used if you want equal height AND equal width columns. It is not meant for any other layouts and is NOT responsive. We can make it fallback however on mobile displays...

<div class="table-row-equal">
<div class="thumbnail">
    Content...
</div>
<div class="thumbnail">
    Content...
</div>
</div>

@media only screen and (min-width : 480px){
    .table-row-equal {
        display: table;
        width: 100%;
        table-layout: fixed;
        border-spacing: 30px 0px;
        word-wrap: break-word;
    }
    .table-row-equal .thumbnail {
        float: none;
        display: table-cell;
        vertical-align: top;
        width: 1%;
    }
}

Lastly, the first demo in the accepted answer which implements a version of the one true layout is a good choice for some situations, but not suitable for bootstrap columns. The reason for this is that all the columns expand to the container height. So this will also break responsiveness since the columns are not expanding to the elements next to them, but the entire container. This method will also not allow you to apply bottom margins to rows any longer and will also cause other issues along the way like scrolling to anchor tags.

有关完整的代码，请参阅自动添加flexbox代码前缀的Codepen。