Spring教程-Spring MVC 表单下拉列表示例
Spring MVC 表单下拉列表
Spring MVC 表单下拉列表包含元素列表。此标签生成 HTML select 元素,允许数据绑定到所选元素。
语法
<form:select path="name">
以下是用于选择选项的其他标签。
option 标签
此标签生成 HTML option 标签。每个标签都包含用户可以选择的值。
<form:option value="abc" label="xyz"/>
options 标签
此标签生成一系列 HTML option 标签。每个标签包含用户选择的元素列表。
语法
<form:options items="${elementList}" itemValue="abc" itemLabel="xyz"/>
Spring MVC 表单下拉列表示例
1. 在 pom.xml 文件中添加依赖项
<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.1.1.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>3.0-alpha-1</version>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.servlet/jstl -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.tomcat/tomcat-jasper -->
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-jasper</artifactId>
<version>9.0.12</version>
</dependency>
2. 创建 Bean 类
Reservation.java
package cn.javatiku;
public class Reservation {
private String firstName;
private String lastName;
private String Gender;
private String[] Food;
private String cityFrom;
private String cityTo;
public Reservation()
{
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getGender() {
return Gender;
}
public void setGender(String gender) {
Gender = gender;
}
public String[] getFood() {
return Food;
}
public void setFood(String[] food) {
Food = food;
}
public String getCityFrom() {
return cityFrom;
}
public void setCityFrom(String cityFrom) {
this.cityFrom = cityFrom;
}
public String getCityTo() {
return cityTo;
}
public void setCityTo(String cityTo) {
this.cityTo = cityTo;
}
}
3. 创建控制器类
ReservationController.java
package cn.javatiku;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
@RequestMapping("/reservation")
@Controller
public class ReservationController {
@RequestMapping("/bookingForm")
public String bookingForm(Model model)
{
//create a reservation object
Reservation res=new Reservation();
//provide reservation object to the model
model.addAttribute("reservation", res);
return "reservation-page";
}
@RequestMapping("/submitForm")
public String submitForm(@ModelAttribute("reservation") Reservation res)
{
return "confirmation-form";
}
}
4. 在 web.xml 文件中提供控制器的入口
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>SpringMVC</display-name>
<servlet>
<servlet-name>spring</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>spring</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
5. 在 XML 文件中定义 Bean
spring-servlet.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd">
<!-- Provide support for component scanning -->
<context:component-scan base-package="cn.javatiku" />
<!--Provide support for conversion, formatting and validation -->
<mvc:annotation-driven/>
<!-- Define Spring MVC view resolver -->
<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/"></property>
<property name="suffix" value=".jsp"></property>
</bean>
</beans>
6. 创建所需页面
index.jsp
<!DOCTYPE html>
<html>
<head>
<title>Railway Registration Form</title>
</head>
<body>
<a href="reservation/bookingForm">Click here for reservation.</a>
</body>
</html>
reservation-page.jsp
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<!DOCTYPE html>
<html>
<head>
<title>Reservation Form</title>
</head>
<h3>Railway Reservation Form</h3>
<body>
<form:form action="submitForm" modelAttribute="reservation">
First name: <form:input path="firstName" />
<br><br>
Last name: <form:input path="lastName" />
<br><br>
Gender:
Male<form:radiobutton path="Gender" value="Male"/>
Female<form:radiobutton path="Gender" value="Female"/>
<br><br>
Meals:
BreakFast<form:checkbox path="Food" value="BreakFast"/>
Lunch<form:checkbox path="Food" value="Lunch"/>
Dinner<form:checkbox path="Food" value="Dinner"/>
<br><br>
Leaving from: <form:select path="cityFrom">
<form:option value="Ghaziabad" label="Ghaziabad"/>
<form:option value="Modinagar" label="Modinagar"/>
<form:option value="Meerut" label="Meerut"/>
<form:option value="Amristar" label="Amristar"/>
</form:select>
<br><br>
Going to: <form:select path="cityTo">
<form:option value="Ghaziabad" label="Ghaziabad"/>
<form:option value="Modinagar" label="Modinagar"/>
<form:option value="Meerut" label="Meerut"/>
<form:option value="Amristar" label="Amristar"/>
</form:select>
<br><br>
<input type="submit" value="Submit" />
</form:form>
</body>
</html>
confirmation-page.jsp
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE html>
<html>
<body>
<p>Your reservation is confirmed successfully. Please, re-check the details.</p>
First Name : ${reservation.firstName} <br>
Last Name : ${reservation.lastName} <br>
Gender: ${reservation.gender}<br>
Meals:
<ul>
<c:forEach var="meal" items="${reservation.food}">
<li>${meal}</li>
</c:forEach>
</ul>
Leaving From : ${reservation.cityFrom} <br>
Going To : ${reservation.cityTo}
</body>
</html>
输出:
以上就是使用 Spring MVC 表单下拉列表创建铁路预订表单的示例。