AJAX提交Struts2表单(服务器端validation校验出错提示)

时间 2021-08-13

标签 javascript css html java jquery ajax apache json 服务器 app 栏目 Ajax 繁體版

原文原文链接

1.目标javascript

在基于Struts2的应用中，利用AJAX方式提交表单实现一个登录验证Action，将服务器端验证结果展示在页面上css

字段错误展现：
html

action 错误提示
java

2.技术实现jquery

利用struts2-jquery插件和struts2-json插件实现
3.实现步骤ajax

3.1依赖jar包
apache

除了struts2-core-2.2.3.jar包之外，还要下载两个jar包json

struts2-jquery-plugin-3.1.0.jar服务器

struts2-json-plugin-2.2.3.jarapp

3.2编写登录处理类Action

这个Action和咱们普通的Action没有任何区别

package com.crazycoder2010.struts2;

import com.opensymphony.xwork2.ActionSupport;

public class LoginAction extends ActionSupport {
	private static final long serialVersionUID = 6627313805146336838L;
	private String name;
	private String password;
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	@Override
	public String execute() throws Exception {
		if(!("Kevin".equals(this.name)&&"111111".equals(this.password))){
			this.addActionError("Wrong!");
		}
		return INPUT;
	}
}

3.3为登录程序添加验证文件LoginAction-Validation.xml(和LoginAction放置在同一个目录下)

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN" "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd">
<validators>
	<field name="name">
		<field-validator type="requiredstring">
			<param name="trim">true</param>
			<message>Name is required.</message>
		</field-validator>
		<field-validator type="stringlength">
			<param name="minLength">2</param>
			<param name="maxLength">60</param>
			<message>Name must be between ${minLength} and ${maxLength} characters long.</message>
		</field-validator>
	</field>
	<field name="password">
		<field-validator type="requiredstring">
			<param name="trim">true</param>
			<message>Password is required.</message>
		</field-validator>
		<field-validator type="stringlength">
			<param name="minLength">2</param>
			<param name="maxLength">60</param>
			<message>Password must be between ${minLength} and ${maxLength} characters long.</message>
		</field-validator>
	</field>
</validators>

3.4配置Action类struts.xml

这个Action的配置有些特殊，注意

a.package须要继承自json-default包

b.action的拦截器引用jsonValidationWorkflowStack

c.result的type类型为json

d.配置该action须要转化成json对象的字段includeProperties

<?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>
	<package name="default" extends="json-default">
		<action name="login" class="com.crazycoder2010.struts2.LoginAction">
			<interceptor-ref name="jsonValidationWorkflowStack"></interceptor-ref>
            <result name="input" type="json">
		  	  	<param name="ignoreHierarchy">false</param>
				<param name="includeProperties">actionErrors\[\d+\], fieldErrors\..+$, actionMessages\[\d+\]</param>
		  	</result>
        </action>
	</package>
</struts>

3.5编写登录页面login.jsp

a.将struts2-jquery的taglib引入页面中

b.在<head>元素中经过<sj:head/>标签引入jquery的css和js文件（这些文件都压缩在struts2-jquery-plugins.jar包中，所以不须要单独下载jquery相关的js了）

c.提交submit按钮改用struts2-jquery插件中的

<sj:submit onCompleteTopics="complete" --在服务器端处理完毕将结果返回到页面时所触发的javascript函数

targets="result" --用来展现结果的容器ID列表，以','分割

onBeforeTopics='clearError' --在将数据提交到服务器端之前所触发的javascript函数，如作一些客户端的验证错误提示信息的清除

返回json结果字符串示例：

{"actionErrors":[],"actionMessages":[],"fieldErrors":{"name":["Name is required."],"password":["Password is required."]}}

<%@ page language="java" contentType="text/html; charset=utf-8"	pageEncoding="utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<%@ taglib prefix="sj" uri="/struts-jquery-tags"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<style type="text/css">
	.errorLabel{color: red;}
</style>
<sj:head jquerytheme="cupertino" ajaxcache="false" compressed="false"/>
</head>
<body>
	<s:form action="login" method="post" theme="simple" namespace="/">
		<ul id="errorMessages"></ul>
		<p>User Name:</p>
		<p><input name="name"/><span id="error_name"></span></p>
		<p>Password:</p>
		<p><input type="password" name="password"/><span id="error_password"></span></p>
		<sj:submit 
			onCompleteTopics="complete" 
			targets="result" 
			onBeforeTopics="clearError"
			value="Login"/>
	</s:form>
<script type="text/javascript">
	$.subscribe('clearError', function(event,data) {
		$("#errorMessages").html("");
		$('.errorLabel').html('').removeClass('errorLabel');
	});
	$.subscribe('complete', function(event,data) {
		$("#errorMessages").html("");//先将上次认证的错误消息清除掉
		$('.errorLabel').html('').removeClass('errorLabel');
		
		var json = $.parseJSON(event.originalEvent.request.responseText);
		if(json.actionErrors && json.actionErrors.length>0){//判断有没有actionErrors
			$.each(json.actionErrors,function(index,data){
				$("#errorMessages").append("<li>"+data+"</li>");
			});
			return;
		}
		if(json.fieldErrors && !isEmpty(json.fieldErrors)){//判断有没有fieldError(LoginAction-validation.xml验证错误)
			$.each(json.fieldErrors,function(index,value){//index就是field的name,value就是该filed对应的错误列表，这里取第一个
				$("#error_"+index).html(value[0]);
				$("#error_"+index).addClass("errorLabel");
			});
			return;
		}
		alert("登录成功");//既没有actionError有没有fieldError则登录成功
	});
	function isEmpty(obj){//判断对象是否为空(处理Object obj = {}这种状况认为isEmpty=true)
		for(var p in obj){
			return false;
		}
		return true;
	}
</script>
</body>