以下示例显示如何在使用Spring Web MVC框架的表单中使用列表框(Listbox)。首先使用Eclipse IDE来创建一个WEB工程,实现一个让用户可选择自己所善长的技术(多选)的功能。并按照以下步骤使用Spring Web Framework开发基于动态表单的Web应用程序:
com.zyiz.springmvc
包下创建两个Java类User
,UserController
。jsp
子文件夹下创建两个视图文件:user.jsp
,userlist.jsp
。完整的项目文件目录结构如下所示 -
User.java 的代码如下所示 -
package com.zyiz.springmvc; public class User { private String username; private String password; private String address; private boolean receivePaper; private String [] favoriteFrameworks; private String gender; private String favoriteNumber; private String country; private String [] skills; public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public boolean isReceivePaper() { return receivePaper; } public void setReceivePaper(boolean receivePaper) { this.receivePaper = receivePaper; } public String[] getFavoriteFrameworks() { return favoriteFrameworks; } public void setFavoriteFrameworks(String[] favoriteFrameworks) { this.favoriteFrameworks = favoriteFrameworks; } public String getGender() { return gender; } public void setGender(String gender) { this.gender = gender; } public String getFavoriteNumber() { return favoriteNumber; } public void setFavoriteNumber(String favoriteNumber) { this.favoriteNumber = favoriteNumber; } public String getCountry() { return country; } public void setCountry(String country) { this.country = country; } public String[] getSkills() { return skills; } public void setSkills(String[] skills) { this.skills = skills; } }
UserController.java 的代码如下所示 -
package com.zyiz.springmvc; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.ModelAttribute; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.servlet.ModelAndView; import org.springframework.ui.ModelMap; @Controller public class UserController { @RequestMapping(value = "/user", method = RequestMethod.GET) public ModelAndView user() { User user = new User(); user.setFavoriteFrameworks((new String []{"Spring MVC","Struts 2"})); user.setGender("M"); ModelAndView modelAndView = new ModelAndView("user", "command", user); return modelAndView; } @RequestMapping(value = "/addUser", method = RequestMethod.POST) public String addUser(@ModelAttribute("SpringWeb")User user, ModelMap model) { model.addAttribute("username", user.getUsername()); model.addAttribute("password", user.getPassword()); model.addAttribute("address", user.getAddress()); model.addAttribute("receivePaper", user.isReceivePaper()); model.addAttribute("favoriteFrameworks", user.getFavoriteFrameworks()); model.addAttribute("gender", user.getGender()); model.addAttribute("favoriteNumber", user.getFavoriteNumber()); model.addAttribute("country", user.getCountry()); model.addAttribute("skills", user.getSkills()); return "userlist"; } @ModelAttribute("webFrameworkList") public List<String> getWebFrameworkList() { List<String> webFrameworkList = new ArrayList<String>(); webFrameworkList.add("Spring MVC"); webFrameworkList.add("Struts 1"); webFrameworkList.add("Struts 2"); webFrameworkList.add("Apache Hadoop"); return webFrameworkList; } @ModelAttribute("numbersList") public List<String> getNumbersList() { List<String> numbersList = new ArrayList<String>(); numbersList.add("1"); numbersList.add("2"); numbersList.add("3"); numbersList.add("4"); return numbersList; } @ModelAttribute("countryList") public Map<String, String> getCountryList() { Map<String, String> countryList = new HashMap<String, String>(); countryList.put("US", "United States"); countryList.put("CH", "China"); countryList.put("SG", "Singapore"); countryList.put("MY", "Malaysia"); return countryList; } @ModelAttribute("skillsList") public Map<String, String> getSkillsList() { Map<String, String> skillList = new HashMap<String, String>(); skillList.put("Hibernate", "Hibernate"); skillList.put("Spring", "Spring"); skillList.put("Apache Hadoop", "Apache Hadoop"); skillList.put("Struts", "Struts"); return skillList; } }
这里的第一个服务方法user()
,我们已经在ModelAndView
对象中传递了一个名称为“command
”的空User
对象,因为如果在JSP文件中使用<form:form>
标签,spring框架需要一个名称为“command
”的对象。 所以当调用user()
方法时,它返回user.jsp
视图。
第二个服务方法addUser()
将根据URL => Listbox/addUser
上的POST方法请求时调用。根据提交的信息准备模型对象。 最后从服务方法返回“userlist
”视图,这将呈现userlist.jsp
视图。
user.jsp 的代码如下所示 -
<%@ page contentType="text/html; charset=UTF-8"%> <%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%> <html> <head> <title>Spring MVC表单处理(列表框)</title> </head> <body> <h2>用户信息</h2> <form:form method="POST" action="/Listbox/addUser"> <table> <tr> <td><form:label path="username">用户名:</form:label></td> <td><form:input path="username" /></td> </tr> <tr> <td><form:label path="password">密码:</form:label></td> <td><form:password path="password" /></td> </tr> <tr> <td><form:label path="address">地址:</form:label></td> <td><form:textarea path="address" rows="5" cols="30" /></td> </tr> <tr> <td><form:label path="receivePaper">是否订阅:</form:label></td> <td><form:checkbox path="receivePaper" /></td> </tr> <tr> <td><form:label path="favoriteFrameworks">喜欢的框架/技术:</form:label></td> <td><form:checkboxes items="${webFrameworkList}" path="favoriteFrameworks" /></td> </tr> <tr> <td><form:label path="gender">性别:</form:label></td> <td><form:radiobutton path="gender" value="M" label="男" /> <form:radiobutton path="gender" value="F" label="女" /></td> </tr> <tr> <td><form:label path="favoriteNumber">喜欢的数字:</form:label></td> <td><form:radiobuttons path="favoriteNumber" items="${numbersList}" /></td> </tr> <tr> <td><form:label path="country">所在国家:</form:label></td> <td><form:select path="country"> <form:option value="NONE" label="请选择..." /> <form:options items="${countryList}" /> </form:select></td> </tr> <tr> <td><form:label path="skills">技术:</form:label></td> <td><form:select path="skills" items="${skillsList}" multiple="true" /></td> </tr> <tr> <td colspan="2"><input type="submit" value="提交" /></td> </tr> </table> </form:form> </body> </html>
这里使用<form:select />
及其属性 multiple=true
标签来呈现HTML列表多选框。 例如 -
<form:select path="skills" items="${skillsList}" multiple="true" />
它将呈现以下HTML内容。
<select id="skills" name="skills" multiple="multiple"> <option value="Struts">Struts</option> <option value="Hibernate">Hibernate</option> <option value="Apache Wicket">Apache Hadoop</option> <option value="Spring">Spring</option> </select> <input type="hidden" name="_skills" value="1"/>
userlist.jsp 的代码如下所示 -
<%@ page contentType="text/html; charset=UTF-8"%> <%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%> <html> <head> <title>Spring MVC表单处理(列表框)</title> </head> <body> <h2>提交用户信息 -</h2> <table> <tr> <td>用户名:</td> <td>${username}</td> </tr> <tr> <td>密码:</td> <td>${password}</td> </tr> <tr> <td>地址:</td> <td>${address}</td> </tr> <tr> <td>是否订阅:</td> <td>${receivePaper}</td> </tr> <tr> <td>喜欢的技术/框架:</td> <td> <% String[] favoriteFrameworks = (String[]) request.getAttribute("favoriteFrameworks"); for (String framework : favoriteFrameworks) { out.println(framework); } %> </td> </tr> <tr> <td>性别:</td> <td>${(gender=="M"? "男" : "女")}</td> </tr> <tr> <td>喜欢的数字:</td> <td>${favoriteNumber}</td> </tr> <tr> <td>国家:</td> <td>${country}</td> </tr> <tr> <td>技术:</td> <td> <% String[] skills = (String[]) request.getAttribute("skills"); for (String skill : skills) { out.println(skill); } %> </td> </tr> </table> </body> </html>
完成创建源和配置文件后,发布应用程序到Tomcat服务器。
现在启动Tomcat服务器,现在尝试访问URL => http://localhost:8080/Listbox/user ,如果Spring Web应用程序没有问题,应该看到以下结果:
提交所需信息后,点击提交按钮提交表单。 如果Spring Web应用程序没有问题,应该看到以下结果: