spingMVC后台数据校验

1.导入jar包（）

 

 

 

2.在实体类中对应属性上加注解

       @NotEmpty(message="账号不能为空")

       private String name;

       @NotEmpty(message="密码不能为空")

       @Length(min=6,max=12,message="密码在[6-12]之间")

       private String password;

       @NotEmpty(message="手机号不能为空")

       @Pattern(regexp="^1[3|4|5|7|8][0-9]\\d{4,8}$",message="手机号格式不正确")

       private String phone;

       @NotNull(message="年龄不能为空")

       @Digits(integer=2,fraction=2,message="数只能有两个整数")

       private Integer age;

 

3.在控制层接收参数（@Valid User2 user,BindingResult br，这两个参数要靠在一起）

       @RequestMapping("register")

       public String register(@Valid User user,BindingResult br,HttpServletRequest request) {

              if(br.hasErrors()) {

                     List<FieldError> fieldErrors=br.getFieldErrors();

                     Map<String,Object> errorMsg=new HashMap<>();

                     for(FieldError f:fieldErrors) {

                            errorMsg.put(f.getField(), f.getDefaultMessage());

                     }

                     request.setAttribute("errorMsg", errorMsg);

                     return "forward:/register.jsp";

              }

              System.out.println(user);

              return "register";

       }

       在jsp中显示

<form action="/SpringMVC/user/register" method="post">

       name:<input type="text" name="name"/>${errorMsg.name }<br/>

       password:<input type="password" name="password"/>${errorMsg.password }<br/>

       phone:<input type="text" name="phone"/>${errorMsg.phone }<br/>

       age:<input type="text" name="age"/>${errorMsg.age }<br/>

       photo:<input type="file" name="photo"/>${errorMsg.photo }<br/>

       <input type="submit" value="提交"/><br/>

</form>