forms - Bootstrap : Vertically center label in form-group

Question

我在水平表单中有一个表单组。在这个表单组中，右边的元素高于左边的元素。出于这个原因，我想在其行中垂直居中左侧元素。例如:

<form class="form-horizontal">
    <div class="form-group">
      <label for="inputEmail3" class="col-sm-2 control-label">Email1</label>
      <div class="col-sm-10"> <!-- higher element -->
        <input type="email" class="form-control" id="inputEmail3" placeholder="Email">
        <br>Random stuff
      </div>
    </div>
    <div class="form-group">
      <label for="inputEmail3" class="col-sm-2 control-label">Email2</label>
      <div class="col-sm-10"> 
        <input type="email" class="form-control" id="inputEmail3" placeholder="Email">
      </div>
    </div>
</form> 

Email1当前显示在其自身行的顶部，如 this plunker snippet 所示.

编辑:所以为了澄清我的意图，这是当前状态:



这就是我想要的(蓝色区域是前面提到的“行”):

Answer 1

如果您准备放弃对某些“旧”浏览器的支持，您可以使用 flexbox 功能(参见 caniuse.com flex)

<div class="form-group flex-group">
  <label for="inputEmail3" class="col-sm-2 control-label">Email1</label>
  <div class="col-sm-10">
    <input type="email" class="form-control" id="inputEmail3" placeholder="Email">
    <br>Random stuff
  </div>
</div>

@media (min-width: 768px) {
  .flex-group {
    display: -webkit-flex;
    display: flex;
    -webkit-align-items: center;
            align-items: center;
  }
  .form-horizontal .flex-group .control-label {
    padding-top: 0;
  }
}

http://plnkr.co/edit/BQ6C4LGiL4oe1ZQTQ3Ys