StringMVC 中如何做数据校验

步骤一：引入四个jar包

步骤二：注册类型转换器

 <context:component-scan base-package="cn.happy.controller"></context:component-scan><!-- 配置验证器 --><bean id="myvalidator" class="org.springframework.validation.beanvalidation.LocalValidatorFactoryBean"><property name="providerClass" value="org.hibernate.validator.HibernateValidator"></property></bean> <mvc:annotation-driven validator="myvalidator"/>

步骤三：为实体类进行注解约束

package cn.happy.entity;import javax.validation.constraints.Max;
import javax.validation.constraints.Min;
import javax.validation.constraints.Pattern;
import javax.validation.constraints.Size;import org.hibernate.validator.constraints.NotEmpty;
/*** @Min最小值* @Max最大值* @NotEmpty 不允许为空* @Pattern 使用正则校验* @Size 长度*/
public class UserInfo {//必须是0到100之间@Min(value=0,message="成绩最小值为{value}")@Max(value=100,message="成绩最大值为{value}")@NotEmpty(message="成绩不允许为空")  private Integer score;//手机号码必须不能为空,必须是以1 开头 第二位3,4,5,6,7,8,9   最后9位随意@NotEmpty(message="手机号码不允许为空")  @Pattern(regexp="^1[3,4,5,6,7,8,9]\\d{9}$",message="手机号码不正确")private String phone;//不能为空//必须是6个字符以上@NotEmpty(message="用户名不能为空") @Size(min=6,message="名称至少6个字符")private String name;public Integer getScore() {return score;}public void setScore(Integer score) {this.score = score;}public String getPhone() {return phone;}public void setPhone(String phone) {this.phone = phone;}public String getName() {return name;}public void setName(String name) {this.name = name;}}

步骤四：编写Handler控制器

package cn.happy.controller;import javax.validation.Valid;import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;import cn.happy.entity.UserInfo;@Controller
public class FirstController {@RequestMapping("/first.do")public ModelAndView doFirst(@Valid UserInfo info,BindingResult br){ModelAndView mv=new ModelAndView();mv.setViewName("/WELCOME.jsp");//记录到底是哪个字段验证失败了//有一个可以侦测到验证错误总数的方法int errorCount = br.getErrorCount();if (errorCount>0) {//证明模型验证失败FieldError score = br.getFieldError("score");FieldError name = br.getFieldError("name");FieldError phone = br.getFieldError("phone");if (score!=null) {mv.addObject("scoremsg",score.getDefaultMessage());}if (name!=null) {mv.addObject("namemsg",name.getDefaultMessage());}if (phone!=null) {mv.addObject("phonemsg",phone.getDefaultMessage());}mv.setViewName("/index.jsp");}//高中  英文版的吻别return mv ;}
}