J2EE 3.10

用户登录增删改查

main.html

top.html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>top.html</title> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="this is my page"> <meta http-equiv="content-type" content="text/html; charset=UTF-8">

</head> <body> This is top page. <br> </body> </html>

left.html

<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <link href="css/amcss.css" rel="stylesheet" type="text/css"> <script language="JavaScript"> function show(i){ if (i.style.display == "none") { i.style.display = ""; }else{ i.style.display = "none"; } } </script>

</head>

right.html

This is right!

add-users.html

<h1>添加用户信息</h1>

</form>

add-users.jsp

<%@page pageEncoding="gb2312" import="java.sql.*"%>
<%
//提取
String u=request.getParameter("uname");
String p=request.getParameter("upass");
String e=request.getParameter("email");
//添加到db/user表中
//注：1、。jar包放到web-inf/lib文件夹中; 2、导入java.sql.*包

try{
  Class.forName("org.gjt.mm.mysql.Driver");
  String url="jdbc:mysql://localhost:3306/db";//db数据库名
  Connection con=DriverManager.getConnection(url,"root","123456");
  String sql="insert into user1 values(?,?,?)";
  PreparedStatement pstm=con.prepareStatement(sql);
  pstm.setString(1,u);//设置参数
  pstm.setString(2,p);
  pstm.setString(3,e);
  pstm.executeUpdate();//执行语句
  pstm.close();//关闭语句

}catch(Exception ex)
{

}

%>

delete-users-do.jsp

<%@page import="java.sql.*"%>
<%
String u=request.getParameter("uname");

try{
  Class.forName("org.gjt.mm.mysql.Driver");
  String url="jdbc:mysql://localhost:3306/db";
  Connection con=DriverManager.getConnection(url,"root","123456");
  String sql="delete from user1 where uname=?";
  PreparedStatement pstm=con.prepareStatement(sql);
  pstm.setString(1,u);
  pstm.executeUpdate();
  pstm.close();
  con.close();

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

%>

delete-users.jsp

<%@page pageEncoding="gb2312" import="java.sql.*"%>
<form action="delete-users-do.jsp" method="get">
请输入要删除的用户名：<input type="text" name="uname">
<input type="submit" value="删除">
</form>

查询：

list-users.html

<form action="list-users.jsp" method="get"> 请输入用户名：<input type="text" name="uname"> <input type="submit" value="查询"> </form>

list.users.jsp

<%@page pageEncoding="gb2312" import="java.sql.*"%>

<% String u=request.getParameter("uname"); try{ Class.forName("org.gjt.mm.mysql.Driver"); String url="jdbc:mysql://localhost:3306/db"; Connection con=DriverManager.getConnection(url,"root","123456"); String sql="select uname,upass,email from user1 where uname like '%"+u+"%'"; PreparedStatement pstm=con.prepareStatement(sql); //pstm.setString(1,u); ResultSet rs=pstm.executeQuery();//查询结果集 //out.println("用户名 "+"密码 "+"Email "+"<br>"); %> <table border=1> <tr> <th>用户名</th> <th>密码</th> <th>Email</th> </tr> <% while(rs.next()) { %> <tr> <td><%=rs.getString(1)%></td> <td><%=rs.getString(2)%></td> <td><%=rs.getString(3)%></td> </tr> <%

//out.println(rs.getString(1)+" "+rs.getString(2)+" "+rs.getString(3)+"<br>"); } }catch(Exception e) { e.printStackTrace(); } %>

modify-users.html

<form action="modify-users.jsp" method="get">
请输入用户名：<input type="text" name="uname">
<input type="submit" value="查询">
</form>

modify-users.jsp

<%@page pageEncoding="gb2312" import="java.sql.*"%>

<% String u=request.getParameter("uname"); try{ Class.forName("org.gjt.mm.mysql.Driver"); String url="jdbc:mysql://localhost:3306/db"; Connection con=DriverManager.getConnection(url,"root","123456"); String sql="select uname,upass,email from user1 where uname=?"; PreparedStatement pstm=con.prepareStatement(sql); pstm.setString(1,u); ResultSet rs=pstm.executeQuery(); if(rs.next()) { %> <form action="modify-users-do.jsp" method="get"> 用户名：<input type="text" name="uname" value=<%=rs.getString(1)%>><br> 密码：<input type="text" name="upass" value=<%=rs.getString(2)%>><br> Email:<input type="text" name="upass" value=<%=rs.getString(2)%>><br> <input type="submit" value="保存"> </form> <% } }catch(Exception e) { e.printStackTrace(); } %>