jsp 管理员登录界面与登录验证

验证分两种情况，成功，进入管理员页，可以看信息和删记录

失败，直接给出登录失败，然后重新登录
login.jsp

java 复制代码

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    
    <%
    //登录
    //将号和密码包为user对象    
    //查user对象是否存在    
    //如果再切换到管理页
    //如果不再继续返回login.jsp页    
    %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>登录</title>
</head>
<body>
<form action="dologin.jsp" method="post">
	用户名:<input type="text" name="uname" required="required" size="20" value="">
	<br>
	密&nbsp;&nbsp;&nbsp;码:<input type="password" name="upwd" required="required" size="20">
	<br>
	<input type="submit" />&nbsp;&nbsp;&nbsp;&nbsp;
	<input type="reset" />
</form>

</body>
</html>

dologin.jsp

java 复制代码

<%@page import="org.apache.tomcat.dbcp.dbcp2.PStmtKey"%>
<%@page import="java.sql.PreparedStatement"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    
    <%@ page import="
java.util.Date,
java.io.IOException,
java.io.PrintWriter,
java.sql.*
" %>

<%@ page import="src.User"
     %>
     
<%
//将传过来的信息 包在值类里
User you=new User();//登录的人的信息包装成对象
you.setName(request.getParameter("uname"));
you.setPwd(request.getParameter("upwd"));
%>
     
<%
 //1.导入jar包
 //2.注册驱动
 //Class.forName("com.mysql.jdbc.Driver");
 Class.forName("com.mysql.cj.jdbc.Driver");

 //3.获取连接
 Connection con = DriverManager.getConnection("jdbc:mysql://mysql.sqlpub.com:3306/huangjin","laocooon","fc12f7a5215e8e0a");

 //4.获取执行者对象
 String sql = "SELECT * FROM adminuser WHERE uname = ?";
 
 PreparedStatement pstmt = con.prepareStatement(sql);
 
 pstmt.setString(1, you.getName());//给第一个参数为用户名
 
 //5.执行sql语句，并且接收结果 
 ResultSet rs = pstmt.executeQuery();
 
 User fUser= new User();
 //6.遍历记录集
 while(rs.next()){
	 fUser.setId(rs.getInt(1));
	 fUser.setName(rs.getString(2));
	 fUser.setPwd(rs.getString(3));
 }
 
 
 // 7 各种关闭
 rs.close();
 pstmt.close();
 con.close();
 
 //找到用户名，现在分析密码对不对
 if(fUser.getPwd().equals(you.getPwd())){
	//由于 此信息需要整体网站需要，所以使用session处理
	 session.setAttribute("adminuser",fUser);
	 
	 //如果没有找到记录，说明 fUser的id是0
	 if(fUser.getId()==0)
		 response.sendRedirect("./error.html");
	 else
		 response.sendRedirect("./adminuser.jsp");	 
 }
 else
	 response.sendRedirect("./error.html");
	 
 
 
  






%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>验证登录是否成功</title>
</head>
<body>

</body>
</html>

error.html

java 复制代码

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>登录失败 </title>
<!--
<style type="text/css">
p{
text-align: center;
font-size: 24px;
color:red;
}

</style>
  -->
  
<link href="./css/myCss.css" rel="stylesheet" type="text/css" />
</head>
<body>
<p>登录失败</p> 
<p><a href="./login.jsp">重新登录</a></p>
</body>
</html>