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根据我上面的几个小积累，其实平时饿get和post已经没问题了，有个特殊的post就是登陆。大家知道登陆问题在server端是session的问题，在客户端来post的时候其实还是cookie的问题，如何把cookie发送到server，并且server认为你是登陆成功了呢。这里给个例子，其实就是CookieContainer的使用，这个使用只需要附带进去就好了。也就是第一次请求的时候附带个空的给request，再次request的时候还是把这个给设置到request中去即可，第一次request带个空的去后，服务器端就把cookie的信息写到了这个container中了，你再次带这个container去request的话，服务器如果还是会从这个container里面找cookie或者再次放入点cookie的。整个代码如下，先发c#的模拟。再次发server端的验证代码：

using System;using System.Collections.Generic;using System.Text;using System.Net;using System.IO;using System.Collections.Specialized; namespace post_test{    class Program    {        static void Main(string[] args)        {            Console.WriteLine("Begin...");            Console.WriteLine("打开登陆页面...");            // 设置cookie的container            CookieContainer cookieContainer = new CookieContainer();            // 设置一些公用的请求头            NameValueCollection collection = new NameValueCollection();            collection.Add("accept-language", "zh-cn,zh;q=0.5");            collection.Add("accept-encoding", "gzip,deflate");            collection.Add("accept-charset", "GB2312,utf-8;q=0.7,*;q=0.7");            collection.Add("cache-control", "max-age=0");            collection.Add("keep-alive", "115");            // 先请求登陆页面            HttpWebRequest requestLoginPage = (HttpWebRequest)WebRequest.Create("http://localhost:8080/test2/index.jsp");            requestLoginPage.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";            requestLoginPage.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.2.13) Gecko/20101203 Firefox/3.6.13";            requestLoginPage.Headers.Add(collection);            HttpWebResponse responseLoginPage = (HttpWebResponse)requestLoginPage.GetResponse();            Console.WriteLine("打开登陆页面状态:{0}", responseLoginPage.StatusCode);            // 来Post数据到登陆页面            HttpWebRequest requestLoginToPage = (HttpWebRequest)WebRequest.Create("http://localhost:8080/test2/servlet/LoginServlet");            requestLoginToPage.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";            requestLoginToPage.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.2.13) Gecko/20101203 Firefox/3.6.13";            requestLoginToPage.ContentType = "application/x-www-form-urlencoded";            requestLoginToPage.Method = "POST";            requestLoginToPage.Headers.Add(collection);            requestLoginToPage.CookieContainer = cookieContainer;            String data = "userName=admin&password=123456";            byte[] bytes = Encoding.ASCII.GetBytes(data);            requestLoginToPage.ContentLength = bytes.Length;            Stream streamLoginToPage = requestLoginToPage.GetRequestStream();            streamLoginToPage.Write(bytes, 0, bytes.Length);            streamLoginToPage.Flush();            streamLoginToPage.Close();            HttpWebResponse responseLoginToPage = (HttpWebResponse)requestLoginToPage.GetResponse();            Console.WriteLine("Post数据结果状态:{0}", responseLoginToPage.StatusCode);            // 打开登陆状态页面            HttpWebRequest requestResultPage = (HttpWebRequest)WebRequest.Create("http://localhost:8080/test2/result.jsp");            requestResultPage.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";            requestResultPage.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.2.13) Gecko/20101203 Firefox/3.6.13";            requestResultPage.Headers.Add(collection);            requestResultPage.CookieContainer = cookieContainer;            HttpWebResponse responseResultPage = (HttpWebResponse)requestResultPage.GetResponse();            Console.WriteLine("打开状态页面状态:{0},内容:{1}", responseLoginPage.StatusCode, new StreamReader(responseResultPage.GetResponseStream(), Encoding.UTF8).ReadToEnd());            Console.Read();        }    }}

1：登陆页面

<%@ page language="java"  pageEncoding="utf-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%>              	
   	
   	
       	
   	
   	
             
   
    	
    
    		     
      
    			       
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package com.baseframework.servlet;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class LoginServlet extends HttpServlet {	/**	 * The doGet method of the servlet. 
	 *	 * This method is called when a form has its tag value method equals to get.	 * 	 * @param request the request send by the client to the server	 * @param response the response send by the server to the client	 * @throws ServletException if an error occurred	 * @throws IOException if an error occurred	 */	public void doGet(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		doPost(request, response);	}	/**	 * The doPost method of the servlet. 
	 *	 * This method is called when a form has its tag value method equals to post.	 * 	 * @param request the request send by the client to the server	 * @param response the response send by the server to the client	 * @throws ServletException if an error occurred	 * @throws IOException if an error occurred	 */	public void doPost(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		response.setContentType("text/html");		PrintWriter out = response.getWriter();		String userName = request.getParameter("userName");		String password = request.getParameter("password");		if(userName != null && password != null && userName.equals("admin") && password.equals("123456")) {			request.getSession().setAttribute("login", "true");			// 添加一个session来验证cookie的效果			request.getSession().setAttribute("count", "123456");			out.println("登陆成功!");			System.out.println("登陆成功!");		} else {			request.getSession().setAttribute("login", "false");			out.println("登陆失败!");			System.out.println("登陆失败!");		}		out.flush();		out.close();	}}

<%@ page language="java" pageEncoding="UTF-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%>                  	
   	
   	
       	
   	
   	
             <%    	if(session.getAttribute("login") != null && session.getAttribute("login").equals("true")) {    		out.println("登陆成功！");    		// 打印测试session    		out.println("[测试Session的count:" + session.getAttribute("count") + "]");    		    	} else {    		out.println("失败！");    	}	    %>  

再次上个运行截图吧：

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