我目前正在开发一个 Java Web 动态项目，我的 html 页面中有一个菜单栏。当用户单击菜单上出现的可用选项之一时，我希望能够控制匹配的 Servlet 中的代码的哪一部分将被执行。
最佳答案
您的菜单项与一个链接相关联，类似于:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>simple Servlet</title>
</head>
<body>
<ul>
<li><a href="action?action=doThat">that Action</a></li>
<li><a href="action?action=doThis">this Action</a></li>
</ul>
</body>
</html>
部署描述符:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
version="3.0">
<servlet>
<servlet-name>action</servlet-name>
<servlet-class>de.so.ActionServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>action</servlet-name>
<url-pattern>/action</url-pattern>
</servlet-mapping>
</web-app>
servlet 代码:
package de.so;
import java.io.IOException;
import java.io.Writer;
import javax.servlet.ServletException;
import javax.servlet.http.*;
public class ActionServlet extends HttpServlet
{
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException,
IOException
{
String action = request.getParameter("action");
Writer out=response.getWriter();
if (action == null || action.isEmpty())
{
out.write("Action empty");
}
else if (action.equals("doThis"))
{
out.write("perform this Action");
}
else if (action.equals("doThat"))
{
out.write("perform that Action");
}
}
}
关于java - 选择将执行哪部分代码，取决于用户的选择，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/37897957/