idea 连接数据库实现对数据库的增删改查 数据库截图 表格截图 user Bean user.java代码``
package com.name; public class user { private String username; private String password; private String gender; private int age; public String getUsername() { return username; } public void setUsername(String username){ this.username=username; } public String getPassword() { return password; } public void setPassword(String password) { this.password= password; } public String getGender() { return gender; } public void setGender(String gender) { this.gender= gender; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } }index代码``
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>$Title$</title> </head> <body> <form method="post" action="register.jsp"> 用户名：<input type="text" name="username"><br> 密码：<input type="text" name="password"><br> 性别：<input type="text" name="gender"><br> 年龄：<input type="text" name="age"><br> <button type="submit">注册</button> </form> </body> </html>增加数据库用户代码
<jsp:useBean id="user" class="com.name.user"> </jsp:useBean <jsp:setProperty name="user" property="*"></jsp:setProperty> <% Class.forName("com.mysql.jdbc.Driver"); String url ="jdbc:mysql://127.0.0.1:3306/book?user=root&password=root"; Connection connection = DriverManager.getConnection(url); String sql = "insert into user (username,password,gender,age) values ('"+user.getUsername()+"','"+user.getPassword()+"',1,23)"; Statement stmt = connection.createStatement(); int count = stmt.executeUpdate(sql); if(count == 0){ out.print("注册失败"); }else{ out.print("注册成功"); } %> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <jsp:useBean id="user" class="com.name.user"></jsp:useBean> <jsp:setProperty name="user" property="*"></jsp:setProperty> <% Class.forName("com.mysql.jdbc.Driver"); String url ="jdbc:mysql://127.0.0.1:3306/book"; Connection connection = DriverManager.getConnection(url,"book","book"); String sql = "insert into user(username,password,gender,age) values (?,?,?,?)"; PreparedStatement temt = connection.prepareStatement(sql); temt.setString(1,request.getParameter("username")); temt.setString(2,request.getParameter("password")); temt.setString(3,request.getParameter("gender")); temt.setInt(4,request.getParameter("age")); ResultSet rs = temt.executeQuery();删除数据库用户
<jsp:setProperty name="user" property="*"></jsp:setProperty> <% Class.forName("com.mysql.jdbc.Driver"); String url ="jdbc:mysql://127.0.0.1:3306/book?user=root&password=root" Connection connection = DriverManager.getConnection(url); Statement stmt = connection.createStatement(); String sql="delete from user where id = 4 "; int count = stmt.executeUpdate(sql); if(count == 0){ out.print("删除失败"); }else{ out.print("删除成功"); } %>删除id为4的用户 数据库的查询
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>主页</title> </head> <body> <jsp> <% Class.forName("com.mysql.jdbc.Driver"); String url = "jdbc:mysql://localhost:3306/book"; Connection connection = DriverManager.getConnection(url,"root","root"); String sql = "select * from user where username = ? and password= ?"; PreparedStatement pstm = connection.prepareStatement(sql); pstm.setString(1,request.getParameter("username")); pstm.setString(2,request.getParameter("password")); ResultSet rs=pstm.executeQuery(); /*Statement stmt = connection.createStatement(); String sql = "select * from user"; ResultSet rs = stmt.executeQuery(sql); */ while (rs.next()) { out.print(rs.getString("username")+"-"+rs.getString(2)+ "<br>"); } %> </body> </html>