以Bootstrap 3形式并排设置两个输入字段的正确方法？

Question

我的表格有很多输入字段。为了避免用户在中型和大型屏幕上滚动，我想将一些输入字段并排放置。并非所有字段都必须并排，这就是为什么我不使用内联表单。这是我所拥有的示例：

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script language="javascript" src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<form name="frmDemo" id="frmDemo">
  <div class="form-group required">
    <label class="control-label" for="last"><span class="label label-primary">Last Name:</span></label>
    <input type="text" class="form-control" name="frmDemo_last" id="frmDemo_last" placeholder="Enter Last Name" maxlength="50" required>
  </div>
  <div class="form-group required">
    <label class="control-label" for="first"><span class="label label-primary">First Name:</span></label>
    <input type="text" class="form-control" name="frmDemo_first" id="frmDemo_first" placeholder="Enter First Name" maxlength="50" required>
  </div>
  <div class="form-group">
    <div class="row">
      <div class="col-xs-12 col-sm-6 col-md-6 col-lg-6">
        <label class="control-label" for="plan"><span class="label label-primary">Plan:</span></label>
        <select class="form-control" name="frmDemo_plan" id="frmDemo_plan">
          <option value="">--Choose Plan--</option>
          <option value="1">1</option>
          <option value="2">2</option>
          <option value="3">3</option>
        </select>
      </div>
      <div class="col-xs-12 col-sm-6 col-md-6 col-lg-6">
        <label class="control-label" for="plantext"><span class="label label-primary">Plan Text:</span></label>
        <input type="text" class="form-control" name="frmDemo_plantext" id="frmDemo_plantext" placeholder="Enter Plan Text" maxlength="50">
      </div>
    </div>
  </div>
  <div class="row">
    <div class="form-group col-xs-12 col-sm-6 col-md-6 col-lg-6">
      <label class="control-label" for="gender"><span class="label label-primary">Gender:</span></label>
      <select class="form-control" name="frmDemo_gender" id="frmDemo_gender" required>
        <option value="">--Choose Gender--</option>
        <option value="F">Female</option>
        <option value="M">Male</option>
      </select>
    </div>
    <div class="form-group col-xs-12 col-sm-6 col-md-6 col-lg-6">
      <label class="control-label" for="gender"><span class="label label-primary">Grade:</span></label>
      <select class="form-control" name="frmDemo_grade" id="frmDemo_grade" required>
        <option value="">--Choose Grade--</option>
        <option value="PK">PK</option>
        <option value="00">00</option>
        <option value="01">01</option>
        <option value="02">02</option>
        <option value="03">03</option>
        <option value="04">04</option>
        <option value="05">05</option>
      </select>
    </div>
  </div>
  <div class="row">
    <div class="form-group col-xs-12 col-sm-12 col-md-12 col-lg-12">
      <button type="submit" name="frmDemo_submit" id="frmDemo_submit" class="btn btn-primary">Submit</button>
    </div>
    <div class="form-group col-xs-12 col-sm-12 col-md-12 col-lg-12">
      <div id="frmDemo_message" class="alert message-submit"></div>
    </div>
  </div>
</form>

如您所见，我能够做到这一点，并将字段并排放置。我的问题是这样做的正确方法是什么？我在Plan输入中使用的第一组字段使用form-group div，然后使用row div，然后使用col- div。 Grade和Gender的第二组输入字段使用row div，然后使用form-group col-。两种方法都可以，但是根据Bootstrap规则哪种有效？如果有人可以解释或给我建议，我将不胜感激。谢谢。

Answer 1

没关系。但是，如果您想通过其他方式而不使用Bootstrap行和列，则可以将特定的.form-group定位为CSS样式。我个人这样做是因为它比嵌套许多行和列要干净得多。我只会将行和列用于其他目的。

HTML：

<div class="form-group required">
    <label class="control-label" for="last"><span class="label label-primary">Last Name:</span></label>
    <input type="text" class="form-control" name="frmDemo_last" id="frmDemo_last" placeholder="Enter Last Name" maxlength="50" required>
</div>

<div class="form-group required">
     <label class="control-label" for="first"><span class="label label-primary">First Name:</span></label>
    <input type="text" class="form-control" name="frmDemo_first" id="frmDemo_first" placeholder="Enter First Name" maxlength="50" required>
</div>

<div class="form-group">
    <label class="control-label" for="plan"><span class="label label-primary">Plan:</span></label>
    <select class="form-control" name="frmDemo_plan" id="frmDemo_plan">
        <option value="">--Choose Plan--</option>
        <option value="1">1</option>
        <option value="2">2</option>
        <option value="3">3</option>
    </select>
</div>

<div class="form-group">
    <label class="control-label" for="plantext"><span class="label label-primary">Plan Text:</span></label>
    <input type="text" class="form-control" name="frmDemo_plantext" id="frmDemo_plantext" placeholder="Enter Plan Text" maxlength="50">
</div>

<div class="form-group">
    <label class="control-label" for="gender"><span class="label label-primary">Gender:</span></label>
    <select class="form-control" name="frmDemo_gender" id="frmDemo_gender" required>
        <option value="">--Choose Gender--</option>
        <option value="F">Female</option>
        <option value="M">Male</option>
    </select>
</div>

<div class="form-group">
    <label class="control-label" for="gender"><span class="label label-primary">Grade:</span></label>
    <select class="form-control" name="frmDemo_grade" id="frmDemo_grade" required>
        <option value="">--Choose Grade--</option>
        <option value="PK">PK</option>
        <option value="00">00</option>
        <option value="01">01</option>
        <option value="02">02</option>
        <option value="03">03</option>
        <option value="04">04</option>
        <option value="05">05</option>
    </select>
</div>

<div class="form-group">
    <button type="submit" name="frmDemo_submit" id="frmDemo_submit" class="btn btn-primary">Submit</button>
</div>

<div class="form-group">
    <div id="frmDemo_message" class="alert message-submit"></div>
</div>

CSS：

/* I used nth-child(n+number) pseudoclass selector since you wanted to start from the 3rd div with .form-group class to be side by side with each other. */

.form-group:nth-child(n+3) {
    width:50%;
    float:left;
}

.form-group:nth-child(n+3) input, .form-group:nth-child(n+3) select {
  width:95%;
}