技術標籤：Web

JavaWeb之request的應用

1.獲取請求引數。

package com.harris.servlet;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Arrays;

public
 
 class LoginServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("成功進入請求");
        String username = req.getParameter("username");
        String password =
 
 req.getParameter("password");
        //下面的方法是返回一個數組 如使用checkbox 多選框的時候
        String[] hobbies = req.getParameterValues("hobbies");
        System.out.println(Arrays.toString(hobbies));
        System.out.println(username+":"+password);

       // System.out.println(req.getContextPath());
 

       // resp.sendRedirect("/success.jsp");
         //下面寫不寫/都是對的,/是表示當前應用的目錄 不加/就是相對路徑 req.getRequestDispatcher("/success.jsp").forward(req,resp);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

2.請求轉發。

req.getRequestDispatcher("/success.jsp").forward(req,resp);

請求轉發之後，url不會變，而且請求的引數屬性會新增在url後面。