登录,注册,修改用户名密码,删除用户的实现(前端+后端+数据库)
链接数据库DBConnection.java代码:package com.qcby.db;import java.sql.Connection;import java.sql.DriverManager;public class DBConnection { public static void main(String[] args) { } String driver = "com.mysql.jdbc.Driver"; String url = "jdbc:my