简单的数据验证:使用addFieldError方法和s:fieldError标签简单处理数据校验(一般不使用)
1.编写index.jsp
<?xml version="1.0" encoding="GB18030" ?>
<%@ page language="java" contentType="text/html; charset=GB18030"
pageEncoding="GB18030"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030" />
<base href="<%=basePath %>"/>
<title>Insert title here</title>
</head>
<body>
使用addFieldError方法和s:fieldError标签简单处理数据校验
<a href="user/user!add?name=a" >添加用户</a>
</body>
</html>
2.编写action
package com.bjsxt.struts2.user.action;
import com.opensymphony.xwork2.ActionSupport;
public class UserAction extends ActionSupport {
private String name;
public String add() {
//对name属性进行校验
if(name == null || !name.equals("admin")) {
this.addFieldError("name", "name is error");//调用addFieldError方法,将提示信息存放到value stack contents中
this.addFieldError("name", "name is too long");//查看值栈中的内容,可以同一个name可以对应多个值
return ERROR;
}
return SUCCESS;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
3.struts.xml配置
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" "http://struts.apache.org/dtds/struts-2.0.dtd"> <struts> <constant name="struts.devMode" value="true" /> <package name="user" extends="struts-default" namespace="/user"> <action name="user" class="com.bjsxt.struts2.user.action.UserAction"> <result name="error">/error.jsp</result> </action> </package> </struts>
4.编写error.jsp,使用struts的标签获取错误信息
<?xml version="1.0" encoding="GB18030" ?>
<%@ page language="java" contentType="text/html; charset=GB18030"
pageEncoding="GB18030"%>
<%@taglib uri="/struts-tags" prefix="s" %><!--使用struts2的标签-->
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030" />
<title>Insert title here</title>
</head>
<body>
User Add Error!
<!--提示信息会有默认的样式,不实用。可以从浏览器中查看源码-->
<s:fielderror fieldName="name" theme="simple"/><!--获取value stack contents的数据-->
<br />
<s:property value="errors.name[0]"/><!--使用OGNL表达式获取value stack contents中的内容-->
<s:debug></s:debug><!--使用这个标签可以查看value stack contents中的数据-->
</body>
</html>