Bootstrap 表单帮助
表单helper类
Bootstrap中有几个“helper”类可用帮助正确显示表单。
要使用户在输入字段中输入无效值时显示一些自定义文本，请使用带有help-block类的span元素。
当输入值无效时，.help-block将出现在其对应的输入字段的下方。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Example of Twitter Bootstrap 3 Block Help Text</title>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/css/bootstrap-theme.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/js/bootstrap.min.js"></script>
<style type="text/css">
.bs-example{
margin: 20px;
}
</style>
</head>
<body>
<div class="bs-example">
<form>
<input type="text" class="form-control">
<span class="help-block">A block of help text that breaks onto a new line and may extend beyond one line.</span>
</form>
</div>
</body>
</html>静态表单控件
要在水平表单布局中的表单标签旁边放置纯文本，请在<p>元素上使用.form-control-static类。
<!DOCTYPE html>
<html lang="en">
<head>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/css/bootstrap-theme.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/js/bootstrap.min.js"></script>
<style type="text/css">
.bs-example{
margin: 20px;
}
/* Fix alignment issue of label on extra small devices in Bootstrap 3.2 */
.form-horizontal .control-label{
padding-top: 7px;
}
</style>
</head>
<body>
<div class="bs-example">
<form class="form-horizontal">
<div class="form-group">
<label for="inputEmail" class="control-label col-xs-2">Email</label>
<div class="col-xs-10">
<p class="form-control-static">harrypotter@mail.com</p>
</div>
</div>
<div class="form-group">
<label for="inputPassword" class="control-label col-xs-2">Password</label>
<div class="col-xs-10">
<input type="password" class="form-control" id="inputPassword" placeholder="Password">
</div>
</div>
<div class="form-group">
<div class="col-xs-offset-2 col-xs-10">
<div class="checkbox">
<label><input type="checkbox"> Remember me</label>
</div>
</div>
</div>
<div class="form-group">
<div class="col-xs-offset-2 col-xs-10">
<button type="submit" class="btn btn-primary">Login</button>
</div>
</div>
</form>
</div>
</body>
</html>