user Bean.java
package com.media.bean; public class UserBean { private String username; private String password; private int gender; private int age; private int status; 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 int getGender() { return gender; } public void setGender(int gender) { this.gender = gender; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public int getStatus() { return status; } public void setStatus(int status) { this.status = status; } }注册页面
<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>使用Statement在数据库增加用户
<% UserBean user = new UserBean(); user.setUsername(request.getParameter("username")); user.setPassword(request.getParameter("password")); 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 = "insert into user (username,password,gender,age) values('"+user.getUsername()+"','"+user.getPassword()+"',1,23)"; int count = stmt.executeUpdate(sql); if(count == 0 ){ out.print("注册失败"); }else{ out.print("注册成功"); } %>使用PreparedStatement语句增加用户
使用Statement删除用户
<% 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"); } %>
使用PreparedStatement删除用户
<% Class.forName("com.mysql.jdbc.Driver"); String url = "jdbc:mysql://localhost:3306/book"; Connection connection = DriverManager.getConnection(url,"root","root"); String sql = "delete from user where id = ? "; PreparedStatement pstm = connection.prepareStatement(sql); pstm.setInt(5); %>使用Statement语句修改用户 现在要修改id为1的用户stadius的值为2
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 = "update user set stadius = 3 where id= 3"; int count = stmt.executeUpdate(sql); if(count == 0){ out.print("修改失败"); }else{ out.print("修改成功"); } %>使用PreparedStatement语句修改用户 现在要修改id为2的用户stadius的值为3
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="update user set statius=? where statius=?"; PreparedStatement pstm=connection.prepareStatement(sql); pstm.setString(2,3);使用Statement查询用户
<% Class.forName("com.mysql.jdbc.Driver"); //建立数据库连接 String url = "jdbc:mysql://127.0.0.1:3306/book?user=root&password=root"; Connection connection = DriverManager.getConnection(url);//获得链接对象 Statement stmt = connection.createStatement(); //用户名username为123 String sql = "select * from user "; ResultSet rs = stmt.executeQuery(sql); while (rs.next()){ out.print(rs.getString("username")+"-"+rs.getString(2)+"<br>"); } %>使用PreparedStatement查询用户
<% 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 temt = connection.prepareStatement(sql); temt.setString(1,request.getParameter("username")); temt.setString(2,request.getParameter("password")); ResultSet rs = temt.executeQuery(); while (rs.next()) { out.print(rs.getString("username")+"-"+rs.getString(2)+"<br>"); } %>所有用户 查询的用户
