答案 0 :(得分:0)
您需要启用"多个" select元素中的功能:
<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet"/>
<select multiple class="form-control">
<option>1</option>
<option>2</option>
<option>3</option>
<option>4</option>
<option>5</option>
</select>
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答案 1 :(得分:0)
这是一个例子
Bootstrap v3.7
对于具有<select>
属性的multiple
控件,默认情况下会显示多个选项。
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" >
<select multiple class="form-control">
<option>1</option>
<option>2</option>
<option>3</option>
<option>4</option>
<option>5</option>
</select>
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你可以学习https://getbootstrap.com/docs/3.3/css/#forms
Bootstrap (Currently v4.0.0-beta)
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
<div class="form-group">
<label for="exampleFormControlSelect2">Example multiple select</label>
<select multiple class="form-control" id="exampleFormControlSelect2">
<option>1</option>
<option>2</option>
<option>3</option>
<option>4</option>
<option>5</option>
</select>
</div>
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您可以了解https://getbootstrap.com/docs/4.0/components/forms/#form-controls
答案 2 :(得分:0)
在size
代码中使用select
属性。
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet" />
<select size="7" class="form-control w-100">
<option selected>John</option>
<option>Paul</option>
<option>Ringo</option>
<option>George</option>
</select>
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