Springmvc 简明教程

Spring MVC - TextArea Example

以下示例介绍了如何在表单中使用 TextArea，方法是使用 Spring Web MVC 框架。首先，让我们提供一个可用的 Eclipse IDE，并按照后续步骤使用 Spring Web 框架开发基于动态表单的 Web 应用程序。

The following example explains how to use TextArea in forms using the Spring Web MVC framework. To begin with, let us have a working Eclipse IDE in place and follow the subsequent steps to develop a Dynamic Form based Web Application using the Spring Web Framework.

Step

Description

1

Create a project with a name HelloWeb under a package com.tutorialspoint as explained in the Spring MVC − Hello World chapter.

2

Create Java classes User, UserController under the com.tutorialspointpackage.

3

Create view files user.jsp, users.jsp under jsp sub-folder.

4

The final step is to create the content of the source and configuration files and export the application as explained below.

User.java

package com.tutorialspoint;

public class User {

   private String username;
   private String password;
   private String address;

   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;
   }
}

UserController.java

package com.tutorialspoint;

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() {
      return new ModelAndView("user", "command", new User());
   }

   @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());

      return "users";
   }
}

在这里，对于第一个服务方法 user()，我们在 ModelAndView 对象中传递了一个空白 User 对象，名称为“command”，这是因为如果你在 JSP 文件中使用 <form:form> 标记，则 Spring 框架需要一个名为“command”的对象。因此，当调用 user() 方法时，它将返回 user.jsp 视图。

Here, for the first service method user(), we have passed a blank User object in the ModelAndView object with name "command", because the spring framework expects an object with name "command", if you are using <form:form> tags in your JSP file. So, when the user() method is called, it returns the user.jsp view.

第二个服务方法 addUser() 将相对于 HelloWeb/addUser URL 上的 POST 方法调用。你将根据提交的信息准备模型对象。最后，“users”视图将从服务方法返回，这将导致呈现 users.jsp。

The second service method addUser() will be called against a POST method on the HelloWeb/addUser URL. You will prepare your model object based on the submitted information. Finally, the "users" view will be returned from the service method, which will result in rendering the users.jsp.

user.jsp

<%@taglib uri = "http://www.springframework.org/tags/form" prefix = "form"%>
<html>
   <head>
      <title>Spring MVC Form Handling</title>
   </head>
   <body>

   <h2>User Information</h2>
   <form:form method = "POST" action = "/HelloWeb/addUser">
      <table>
         <tr>
            <td><form:label path = "username">User Name</form:label></td>
            <td><form:input path = "username" /></td>
         </tr>
         <tr>
            <td><form:label path = "password">Age</form:label></td>
            <td><form:password path = "password" /></td>
         </tr>
         <tr>
            <td><form:label path = "address">Address</form:label></td>
            <td><form:textarea path = "address" rows = "5" cols = "30" /></td>
         </tr>
         <tr>
            <td colspan = "2">
               <input type = "submit" value = "Submit"/>
            </td>
         </tr>
      </table>
   </form:form>
   </body>
</html>

在这里，我们使用 <form:textarea /> 标记来呈现 HTML textarea 框。例如：

Here, we are using <form:textarea /> tag to render a HTML textarea box. For example −

<form:textarea path = "address" rows = "5" cols = "30" />

它将呈现以下 HTML 内容。

It will render the following HTML content.

<textarea id = "address" name = "address" rows = "5" cols = "30"></textarea>

users.jsp

<%@taglib uri = "http://www.springframework.org/tags/form" prefix = "form"%>
<html>
   <head>
      <title>Spring MVC Form Handling</title>
   </head>
   <body>

      <h2>Submitted User Information</h2>
      <table>
         <tr>
            <td>Username</td>
            <td>${username}</td>
         </tr>
         <tr>
            <td>Password</td>
            <td>${password}</td>
         </tr>
         <tr>
            <td>Address</td>
            <td>${address}</td>
         </tr>
      </table>
   </body>
</html>

一旦你完成了创建源文件和配置文件，导出你的应用程序。右键单击你的应用程序，使用“导出 → WAR 文件”选项并将你的 HelloWeb.war 文件保存到 Tomcat 的 Webapps 文件夹中。

Once you are done with creating source and configuration files, export your application. Right click on your application, use Export → WAR File option and save your HelloWeb.war file in Tomcat’s webapps folder.

现在，启动 Tomcat 服务器，并确保能够使用标准浏览器从 webapps 文件夹访问其他网页。尝试一个 URL –http://localhost:8080/HelloWeb/user，如果 Spring Web 应用程序一切正常，我们将看到以下屏幕。

Now, start your Tomcat server and make sure you are able to access other webpages from webapps folder using a standard browser. Try a URL –http://localhost:8080/HelloWeb/user and we will see the following screen if everything is fine with the Spring Web Application.

spring textarea

在提交所需信息后，单击“submit”按钮提交表单。如果 Spring Web 应用程序一切正常，我们将会看到以下屏幕。

After submitting the required information, click on the submit button to submit the form. We will see the following screen, if everything is fine with the Spring Web Application.

spring textarea result