有关韩顺平教学视频servlet的学习源码代码（1）

来源：互联网发布：网络用语gb是什么意思编辑：程序博客网时间：2024/06/04 20:59

//实现简单的登陆系统

package com.tsinghua;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;

public class Login extends HttpServlet
{
public void doGet(HttpServletRequest req, HttpServletResponse res)
{

try{
res.setContentType("text/html;charset=GBk"); //这个是解决中文乱码的问题

PrintWriter pw = res.getWriter();

    pw.println("<html>");
    pw.println("<body>");
    pw.println("<h1>登陆界面</h1>");
    pw.println("<form action=LoginC1 method=post>");
    pw.println("用户名：<input type=text name=usrename><br>");
    pw.println("密码:<input type=password name=passwd><br>");
    pw.println("<input type=submit value=loing><br>");
    pw.println("</form>");
    pw.println("</body>");
    pw.println("</html>");
       }
catch(Exception ex)
{
  ex.printStackTrace();
  }

}
}

package com.tsinghua;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;

public class LoginC1 extends HttpServlet
{
public void doGet(HttpServletRequest req, HttpServletResponse res)
{

try{

String u = req.getParameter("usrename");
String p = req.getParameter("passwd");

if (u.equals("sp")&&p.equals("123")){

res.sendRedirect("LoginC2?uname="+u);

               }else{
                    res.sendRedirect("Login");
                 }

       }
catch(Exception ex)
{
  ex.printStackTrace();
  }

}

public void doPost(HttpServletRequest req, HttpServletResponse res)
{

this.doGet( req, res);

}
}//这个不能少，

//显示跳转的登陆信息。

package com.tsinghua;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;

public class LoginC2 extends HttpServlet
{
public void doGet(HttpServletRequest req, HttpServletResponse res)
{
String u=req.getParameter("uname");

try{

PrintWriter pw = res.getWriter();
pw.println("wellcome"+u);

       }
catch(Exception ex)
{
  ex.printStackTrace();
  }

}
}

总结：doGet(HttpServletRequest req, HttpServletResponse res)//req 是获取字符串，res是显示字符串。doGet方法必须要和doPost方法同时使用，漏掉露面的网页部署上会显示路径报错，错误

00: Servlet验证出现405错误，HTTP method POST is not supported by this URL，

string u = req.getParameter("usrename");

string p = req.getParameter("passwd");//res.sendRedirect("wel?nuame="+u+"&upasswd"+p)

有关韩顺平教学视频servlet的学习源码代码（1）

Servlet验证出现405错误，HTTP method POST is not supported by this URL，