using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;//SQL SEVER .NET 資料程式提供程式名稱空間

namespace ConsoleApplication1
{
    class Program
    {
        private const string strconn = @"Data Source=.;Initial Catalog=MySchool;
                        Integrated Security=True";
        static void Main(string[] args)
        {
            
            Program p = new Program();
            p.delu();
           
            //string name = "admin"; //為宣告專案可以不用特意宣告他
            //string pwd = "0";     //為宣告專案可以不用特意宣告他
            //Console.WriteLine("請輸入賬號:");
            //string a = Console.ReadLine();
            //Console.WriteLine("請輸入密碼:");
            //string C = Console.ReadLine();
            //string Msg = " ";
       
            //bool b = p.chech(a, C, ref Msg);
            //if (b)
            //{
            //    p.show();
            //    Console.WriteLine(Msg);


            //}
            //else
            //{
            //    Console.WriteLine("你登陸失敗!!!");
            //}
        
//////////////////////////////////////////////////////////////////////////////////////

        }
        public bool chech(string name,string pwd,ref string Msg) 
        {
            SqlConnection conn = new SqlConnection(strconn);//區域性變數
            try
            {
               // SqlConnection conn = new SqlConnection(strconn);成員變數
                conn.Open();
                string str = @"SELECT COUNT(*) FROM [MySchool].[dbo].[Admin]
                        where LoginId='" + name + "'and LoginPwd='" + pwd + "'";
                Console.WriteLine(str);
                SqlCommand comm = new SqlCommand(str, conn);
                int o = (int)comm.ExecuteScalar(); //強制轉換為 int 型別
                if (o > 0)
                {
                    Msg = "登陸成功";//引用傳參 可以不寫
                    return true;
                }
                Console.WriteLine(o);
            }
            catch (Exception ex)
            {

                Console.WriteLine("出現異常" + ex.Message);
             
            }
            finally 
            {
                conn.Close();  
            }
                
            return false;
        }
        public bool delu() ////登陸賬戶和密碼
        {
            Console.WriteLine("請輸入賬號:");
            string a = Console.ReadLine();
            Console.WriteLine("請輸入密碼:");
            string C = Console.ReadLine();
            string Msg = " ";

            bool b = chech(a, C, ref Msg);
            if (b)
            {
               show();
                Console.WriteLine(Msg);
                return true;


            }
            else
            {
                Console.WriteLine("你登陸失敗!!!");
                Console.WriteLine("請重新輸入");
                return false;
            }


        }
        public void show() /////建立一個選單//////////////////////
        {
            do
            {
                Console.WriteLine("=======請選擇操作鍵======");
                Console.WriteLine("1. 統計學生人數");
                Console.WriteLine("2. 檢視學生名單");
                Console.WriteLine("3. 按學號查詢學生姓名");
                Console.WriteLine("4. 按姓名查詢學生資訊");
                Console.WriteLine("5. 修改學生出生日期");
                Console.WriteLine("6. 刪除學生記錄");
                Console.WriteLine("0. 退出");
                Console.WriteLine("=========================");
                Console.WriteLine("請選擇:");
                int num = int.Parse(Console.ReadLine());
                switch (num)
                {
                    case 1:
                        show1();
                        continue;
                    case 2:
                      
                        continue;
                    case 3:
                     
                        continue; ;
                    case 4:
                       
                        continue;
                    case 5:
                        
                        continue;
                    case 6:
                        
                        continue;
                    case 0:
                      
                        break;
                    default:
                        Console.WriteLine("輸入錯誤");
                        continue;
                }
                break;
            } while (true);


        }
        public void show1() /////查詢學生人數////////////////
        {
            SqlConnection conn = new SqlConnection(strconn);
            try
            {
                string str = "select count(*) from Student";
                conn.Open();
                SqlCommand comm = new SqlCommand(str, conn);
                int i = (int)comm.ExecuteScalar();
                Console.WriteLine("學生總人數為:" + i);

            }
            catch (Exception)
            {

                Console.WriteLine("出現異常");
            }
            finally 
            {
                conn.Close();
            }

        }
    }
}