QQ communication

Claim

实现增删改查功能

Make code display

Start method

  public void start()
    {
    
    
        Console.WriteLine("程序启动了，这是start方法");


        //判断是否登录成功
        if (login())
        {
    
    
            Console.WriteLine("登录成功!");
            Menu();//显示菜单
        }
        else
        {
    
    
            Console.WriteLine("账号或密码错误");
        }



        Console.ReadKey();
    }

Login function method

 public bool login()
    {
    
    
        bool reaf=false;
        Console.WriteLine("登陆功能,被调用的login方法");
        // 接收键盘输入，用户名，密码
        Console.WriteLine("请输入用户名：");
        usr_name = Console.ReadLine();
        Console.WriteLine("请输入密码：");
        string pwd = Console.ReadLine();

        // 去数据表中查询（需要用户表，用户名列，密码列）
        string sql = "select COUNT(*) from QQUser where QQID=" + usr_name + " and PassWord='" + pwd + "';";
        SqlCommand cmd = new SqlCommand(sql, connection);
        connection.Open();
        string a = cmd.ExecuteScalar().ToString();
        Console.WriteLine(a);
        connection.Close();
        if (a.Equals("1"))
        {
    
    
            reaf = true;
        }
        else
        {
    
    
            reaf = false;
        }
        // 如果查询成功，代表登陆成功，给一个返回值
        // 如果查询不成功，登陆失败，给一个返回值
        return reaf;
    }

Display menu method

public void Menu()
{
    
    
    Console.WriteLine("1.查询好友");
    Console.WriteLine("2.删除好友");
    Console.WriteLine("3.添加好友");
    Console.WriteLine("4.修改好友");
    Console.WriteLine("q.退出");

    Console.WriteLine("请选择你要操作的选择");
    string a= Console.ReadLine();
    switch (a) {
    
     
        case "1":
            select_from();//查询方法
            break;
        case "2":

            break;
        case "3":

            break;
        case "4":

            break;
        default:
            break;
    }
}

public void select_from() {
    
    
        string sql = "select * from BaseInfo where qqid=" + usr_name + ";";
        string sql2 = "select count(*) from BaseInfo where qqid=" + usr_name + ";";
        connection.Open();
        
        SqlCommand cmd2 = new SqlCommand(sql2, connection);
        int a = Convert.ToInt32(cmd2.ExecuteScalar().ToString());
        if (a > 0)
        {
    
    
            SqlCommand cmd = new SqlCommand(sql, connection);
            SqlDataReader sdr = cmd.ExecuteReader();
            while (sdr.Read())
            {
    
    
                Console.WriteLine("QQ号：" + sdr["qqid"]);
                Console.WriteLine("昵称：" + sdr["nickname"]);
                Console.WriteLine("年龄：" + sdr["age"]);
            }

        }
        else
        {
    
    
            Console.WriteLine("你没有好友");
        }
        
        connection.Close();
    }