【javaweb】註冊登陸頁面與mysql鏈接後的驗證與傳值

時間 2020-05-22

標籤 javaweb 註冊登陸頁面 mysql 鏈接驗證欄目 Java 简体版

原文原文鏈接

要求：html

　　1）regist.jsp form action method input namejava

　　2) 定義RegisterServlet doGet（）中實現獲取用戶名和密碼獲取到，連數據庫---執行insert into s_user(uname,upwd) values(name,pwd);mysql

　　　　S_user 表中主鍵是自增加的，進行插入操做時不須要給主鍵複製sql

　　3) 響應結果—註冊成功跳轉到login.jsp數據庫

　　4） login.jsp獲取剛註冊的用戶名和密碼app

eclipse界面eclipse

mysql頁面：jsp

注意要點：ide

傳值方法：post

　　　RegisterServlet.java頁面：

　　　request.setAttribute("Rname", RegisterName);

　　　 request.setAttribute("Rpwd", RegisterPwd);

　　　 RequestDispatcher rd=request.getRequestDispatcher("login.jsp");

　　　rd.forward(request, response);

.jsp頁面： value="${Rname}"

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2  pageEncoding="UTF-8"%>
 3 <!DOCTYPE html>
 4 <html>
 5 <head>
 6 <meta charset="UTF-8">
 7 <title>登陸</title>
 8 </head>
 9 <body>
10 <!-- 
11 name屬性表示請求參數名 inputName 12 value屬性表示請求參數值 inputPwd 13 inputName=張三 14 inputPwd=123 15  -->
16  <p>登陸頁面</p>
17     <form action="UserServlet" method="post">
18         用戶名：<input type="text" name="inputName" id="username" placeholder="請輸入用戶名" value="${Rname}" />
19         密碼：<input type="password" name="inputPwd" id="pwd" placeholder="請輸入密碼" value="${Rpwd}" />
20         <!-- 注意input的value值中來自RegisterServlet.java的傳遞方法-->
21             <input type="submit" value="登陸" id="register"/>
22     </form>
23 
24 </body>
25 </html>

 1 <%@ page language="java" contentType="text/html; charset=UTF-8"
 2  pageEncoding="UTF-8"%>
 3 <!DOCTYPE html>
 4 <html>
 5 <head>
 6 <meta charset="UTF-8">
 7 <title>Insert title here</title>
 8 </head>
 9 <body>
10  <p>註冊頁面</p>
11     <form action="RegisterServlet" method="post">
12         用戶名：<input type="text" name="inputName" id="username" placeholder="請輸入用戶名" />
13         密碼：<input type="password" name="inputPwd" id="pwd" placeholder="請輸入密碼" />
14             <input type="submit" value="註冊" id="register"/>
15     </form>
16 </body>
17 </html>


【UserServlet.java頁面】

 1 package com.shoppingmall.servlet;  2 import java.io.IOException;  3 import java.sql.Connection;  4 import java.sql.DriverManager;  5 import java.sql.PreparedStatement;  6 import java.sql.ResultSet;  7 import java.sql.SQLException;  8 import javax.servlet.ServletException;  9 import javax.servlet.annotation.WebServlet; 10 import javax.servlet.http.HttpServlet; 11 import javax.servlet.http.HttpServletRequest; 12 import javax.servlet.http.HttpServletResponse; 13 @WebServlet("/UserServlet") 14 public class UserServlet extends HttpServlet { 15     private static final long serialVersionUID = 1L; 16     public UserServlet() { 17         super(); 18  } 19     protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 20         response.getWriter().append("Served at: ").append(request.getContextPath()); 21         request.setCharacterEncoding("UTF-8"); 22         String name=request.getParameter("inputName"); 23         String pwd=request.getParameter("inputPwd"); 24         boolean flag= false; 25         try{ 26             Class.forName("com.mysql.jdbc.Driver"); 27             String url="jdbc:mysql://localhost:3306/shopping"; 28             String username="root"; 29             String password="111111"; 30             Connection conn=DriverManager.getConnection(url,username,password); 31  System.out.println(conn); 32             String sql = "select  *   from employee  where username = '"+ name +"'  and pwd = '"+ pwd +"' "; 33             PreparedStatement ps=conn.prepareStatement(sql); 34             ResultSet rs=ps.executeQuery(); 35             while(rs.next()){ 36                 System.out.println("驗證成功！"); 37                 flag=true; 38  } 39             if(flag){ 40                 response.sendRedirect("success.jsp"); 41             }else{ 42                 response.sendRedirect("index.jsp"); 43  } 44         }catch(ClassNotFoundException e){ 45  e.printStackTrace(); 46         }catch(SQLException e){ 47  e.printStackTrace(); 48  } 49  } 50     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 51  doGet(request, response); 52  } 53 }

【RegisterServlet.java頁面】

 1 package com.shoppingmall.servlet;  2 import java.io.IOException;  3 import java.sql.Connection;  4 import java.sql.DriverManager;  5 import java.sql.PreparedStatement;  6 import java.sql.ResultSet;  7 import java.sql.SQLException;  8 import javax.servlet.RequestDispatcher;  9 import javax.servlet.ServletException; 10 import javax.servlet.annotation.WebServlet; 11 import javax.servlet.http.HttpServlet; 12 import javax.servlet.http.HttpServletRequest; 13 import javax.servlet.http.HttpServletResponse; 14 @WebServlet("/RegisterServlet") 15 public class RegisterServlet extends HttpServlet { 16     private static final long serialVersionUID = 1L; 17     public RegisterServlet() { 18         super(); 19  } 20     protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 21         response.getWriter().append("Served at: ").append(request.getContextPath()); 22         request.setCharacterEncoding("UTF-8"); 23         response.setContentType("text/html;charset=utf-8"); 24         String RegisterName=request.getParameter("inputName"); 25         String RegisterPwd=request.getParameter("inputPwd"); 26         boolean flag= false; 27         try{ 28             Class.forName("com.mysql.jdbc.Driver"); 29             String url="jdbc:mysql://localhost:3306/shopping"; 30             String username="root"; 31             String password="111111"; 32             Connection conn=DriverManager.getConnection(url,username,password); 33  System.out.println(conn); 34             String sql = "select  *   from employee  where username = '"+ RegisterName +"'  and pwd = '"+ RegisterPwd +"' ";　　//數據庫中查詢是否有 35             PreparedStatement ps=conn.prepareStatement(sql); 36             ResultSet rs=ps.executeQuery(sql); 37             while(rs.next()){ 38                 flag=true; 39  } 40             if(flag){ 41                 System.out.println("您的帳號已存在請直接登陸！"); 42                 request.setAttribute("Rname", RegisterName); 43                 request.setAttribute("Rpwd", RegisterPwd); 44                 RequestDispatcher rd=request.getRequestDispatcher("login.jsp"); 45  rd.forward(request, response); //以上四行是帳號存在時向login.jsp傳值 46             }else{ 47                 String sqlInsert = "insert into employee(username,pwd)"+"values('"+RegisterName+"','"+RegisterPwd+"')";　　//向數據庫中插入數據 48                 PreparedStatement r=conn.prepareStatement(sqlInsert); 49  r.executeUpdate(); 50                 System.out.println("註冊成功！"); 51                 request.setAttribute("Rname", RegisterName); 52                 request.setAttribute("Rpwd", RegisterPwd); 53                 RequestDispatcher rd=request.getRequestDispatcher("login.jsp"); 54  rd.forward(request, response);　　//以上四行是帳號不存在時向login.jsp傳值 55  } 56         }catch(ClassNotFoundException e){ 57  e.printStackTrace(); 58         }catch(SQLException e){ 59  e.printStackTrace(); 60  } 61  } 62     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 63         // TODO Auto-generated method stub
64         response.setCharacterEncoding("UTF-8");　　 65  doGet(request, response); 66  } 67 }