标签：style blog http color io os ar java for
validate（）方法验证
一个ACTION类继承ActionSupport有何用处？
答：在ActionSupport中实现了很
多接口，就拿一个来讲，validate()方法，是默认的验证。我们可以在我们的action类中重写一下此方法。比方说验证用户名是否为空。这个方法
不需要调用，当S：FORM表单提交了，到了action类中会首先执行此方法。对数据进行验证。
用 el 表达式 或 struts 标签 读取错误信息
1 <%@ page language="java" contentType="text/html; charset=ISO-8859-1" 2 pageEncoding="ISO-8859-1"%> 3 <%@ taglib uri="/struts-tags" prefix="s"%> 4 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 5 <html> 6 <head> 7 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> 8 <title>Insert title here</title> 9 <style> 10 span{ 11 color:red;; //css 12 } 13 14 15 </style> 16 </head> 17 <body> 18 <form action="login" method="post"> 19 username:<input type="text" name="username" /><span> ${errors.username[0] }|<s:property value="errors.username[0]"/></span><br /> <br /> 20 password:<input type="password" name="password" /><span>${errors.password[0] }|<s:property value="errors.password[0]"/></span><br /><br /> 21 <input type="submit" value="submit" /> <input type="reset" value="cancel" /> 23 </form> 24 </body> 25 </html>
validate()方法校验
1 package com.helen.action; 2 3 import com.opensymphony.xwork2.ActionSupport; 4 5 public class LoginAction extends ActionSupport { 6 private String username; 7 private String password; 8 9 public void validate() { 10 11 if (username == null || username.equals("")) { 12 this.addFieldError("username", "please enter your username!"); 13 } else if (!username.equals("admin")) { 14 this.addFieldError("username", "username is not right!"); 15 } 16 if (password == null || password.equals("")) { 17 18 this.addFieldError("password", "please enter your password!"); 19 } else if (!password.equals("123")) { 20 this.addFieldError("password", "password is not right!"); 21 } 22 23 } 24 25 public String getUsername() { 26 return username; 27 } 28 29 public void setUsername(String username) { 30 this.username = username; 31 } 32 33 public String getPassword() { 34 return password; 35 } 36 37 public void setPassword(String password) { 38 this.password = password; 39 } 40 41 }
返回值为 input
<action name="login" class="com.helen.action.LoginAction"> <result name="input">/index.jsp</result> <result>/success.jsp</result>
</action>
标签：style blog http color io os ar java for
原文地址：http://www.cnblogs.com/thrive/p/4011372.html
