Bootstrap 表单 http://www.runoob.com/try/try2.php?filename=bootstrap3-form-controlstate （这链接里有简介）
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<link rel="stylesheet" href="http://cdn.bootcss.com/bootstrap/3.3.0/css/bootstrap.min.css" >
</head>
<script src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script>
<script src="http://cdn.bootcss.com/bootstrap/3.3.0/js/bootstrap.min.js"></script>
<style>
.right_20{right:20px;}
</style>
<body>
<div class="width90_">
<form class="form-horizontal bs-example bs-example-form">
<div class="form-group form-group-sm has-success">
<label class="fontSize12 col-sm-4 control-label" for="old_pwd">
<span style = 'color:red;'></span>成功
</label>
<div class="col-sm-6">
<input maxLength = '50' class="form-control" type="text" id="old_pwd" placeholder="" >
<span class="glyphicon glyphicon-ok form-control-feedback right_20"></span>
</div>
</div>
<div class="form-group form-group-sm has-warning">
<label class="fontSize12 col-sm-4 control-label" for="new_pwd">
<span style = 'color:red;'></span>警告
</label>
<div class="col-sm-6">
<input maxLength = '50' class="form-control" type="text" id="new_pwd" placeholder="" >
<span class="glyphicon glyphicon-warning-sign form-control-feedback right_20"></span>
</div>
</div>
<div class="form-group form-group-sm has-error">
<label class="fontSize12 col-sm-4 control-label" for="re_new_pwd">
<span style = 'color:red;'></span>错误
</label>
<div class="col-sm-6">
<input class="form-control" type="text" id="re_new_pwd" placeholder="">
<span class="glyphicon glyphicon-remove form-control-feedback right_20"></span>
</div>
</div>
</form>
</div>
</body>
</html>