JavaScript前端密码验证实现示例

<!DOCTYPE html>
<html lang="en">
<head>
 <meta charset="UTF-8">
 <title>密码验证</title>
 <script src="js/jquery-1.11.1.js"></script>
 <script>
  $(function(){
   $(document).on('blur','input',function(){
    var $password=$('#password').val();
    var $password_again=$('#password_again').val();
     if(!$password){
      $("#password").addClass('redBorder').next('label').show().html('不能为空');;
      return false;
     }else if(!$password_again){
      $("#password_again").addClass('redBorder').next('label').show().html('不能为空');
      return false;
     }else{
      $('input').removeClass('redBorder').next('label').empty();
      if($password_again==$password){
       $("#password,#password_again").next('label').show().html('两次密码一致').addClass('valid');
      }else if($password_again!=$password){
       $("#password,#password_again").addClass('redBorder').next('label').show().html('两次密码不一致').removeClass('valid').addClass('erro');
      }
 
    } 
   })
    
  })
 </script>
 <style>
  .redBorder{
   border: 1px solid red;
  }
  .erro{
   background: url('images/unchecked.gif') no-repeat;
   padding-left: 16px;
  }
  .valid{
   background: url('images/checked.gif') no-repeat;
   width: 16px;
   height: 16px;
  }
 </style>
</head>
<body>
<div>
 <label>
  输入密码：<input type="text" placeholder="输入密码" id="password">
  <label id="password-erro" class="erro" style="display:none;"></label>
 </label>
 <br><br>
 <label>
  验证密码：<input type="text" placeholder="输入相同密码" id="password_again">
  <label id="password-erro" class="erro" style="display:none;"></label>
 </label>
 <br><br>
 <button style="margin-left:80px;">submit</button>
</div> 
</body>
</html>