MVC-- three-tier architecture notes, 1

Three-tier architecture MVC notes 1,

DAL-- data access layer; (specifically interact with the database, check additions are modified in this way; MODEL required reference layer)

BLL-- business logic; (bridge between the pages with the database; required reference DAL, MODEL Layer)

MODEL-- model layer; (a data table corresponding to a Model class field attributes are the same, object-oriented programming, parameters are passed to MODEL; without reference to other layers)

MVC-- page; (CONTROLLER file in a folder corresponding to VIEW, corresponding to the method in CONTROLLER VIEW CSHTML the folder; references required BLL, MODEL Layer)

 

 

DAL Reference Code:

Helper——SqlHelper.cs：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;

namespace DAL.Helper
{
    class SqlHelper
    {
        private static readonly string connString = ConfigurationManager.ConnectionStrings["connString"].ToString();

        /// <summary>
        /// 执行增删改方法
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static int Update(string sql)
        {
            SqlConnection conn = new SqlConnection(connString);
            SqlCommand cmd = new SqlCommand(sql, conn);
            try
            {
                conn.Open();
                return cmd.ExecuteNonQuery();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                conn.Close();
            }
        }

        /// <summary>
        /// 执行返回单一结果查询
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static object GetSingleResult(string sql)
        {
            SqlConnection conn = new SqlConnection(connString);
            SqlCommand cmd = new SqlCommand(sql, conn);
            try
            {
                conn.Open();
                return cmd.ExecuteScalar();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                conn.Close();
            }
        }

        /// <summary>
        /// 执行一个结果集的查询
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static SqlDataReader GetReader(string sql)
        {
            SqlConnection conn = new SqlConnection(connString);
            SqlCommand cmd = new SqlCommand(sql, conn);
            try
            {
                conn.Open();
                return cmd.ExecuteReader(CommandBehavior.CloseConnection);
            }
            catch (Exception ex)
            {
                conn.Close();
                throw ex;
            }
        }
    }
}

View Code

 

SysAdminService.cs：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Models;
using System.Data;
using System.Data.SqlClient;

namespace DAL
{
    public class SysAdminService
    {
        /// <summary>
        /// 根据用户名和密码查询
        /// </summary>
        /// <param name="objAdmin"></param>
        /// <returns></returns>
        public SysAdmin AdminLogin(SysAdmin objAdmin)
        {
            string sql = "SELECT AdminName FROM Admins WHERE LoginId='{0}' AND LoginPwd='{1}'";
            sql = string.Format(sql, objAdmin.LoginId, objAdmin.LoginPwd);
            try
            {
                SqlDataReader reader = Helper.SqlHelper.GetReader(sql);
                if (reader.Read())
                {
                    objAdmin.AdminName = reader["AdminName"].ToString();
                    reader.Close();
                }
                else
                {
                    objAdmin= null ; 
                } 
            } 
            the catch (Exception EX) 
            { 
                the throw  new new Exception ( " application or database error: " + ex.Message); 
            } 
            return objAdmin; 
        } 
    } 
}

View Code

 

BLL reference code:

SysAdminManager.cs:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Models;
using DAL;
using System.Web;

namespace BLL
{
    public class SysAdminManager
    {
        /// <summary>
        /// 根据用户名和密码查询
        /// </summary>
        /// <param name="objAdmin"></param>
        /// <returns></returns>
        public SysAdmin AdminLogin(SysAdmin objAdmin)
        {
            objAdmin = new SysAdminService().AdminLogin(objAdmin);
            if (objAdmin != null)
            {
                HttpContext.Current.Session["CurrentAdmin"] = objAdmin;
            }
            return objAdmin;
        }

    }
}

View Code

 

MODEL reference code:

SysAdmin.cs：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Models
{
    /// <summary>
    /// 管理员类
    /// </summary>
    [Serializable]
    public class SysAdmin
    {
        public string LoginId { get; set; }
        public string AdminName { get; set; }
        public string LoginPwd { get; set; }

    }
}

View Code

 

MVC - Controllers Reference Code:

SysAdminController.cs：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Models;
using BLL;

namespace StudentManagerMVC.Controllers
{
    public class SysAdminController : Controller
    {
        // GET: SysAdmin
        public ActionResult Index()
        {
            return View("AdminLogin");
        }

        public ActionResult AdminLogin()
        {
            if (string.IsNullOrEmpty(Request.Params["loginId"].ToString()) || string.IsNullOrEmpty(Request.Params["loginPwd"].ToString()))
            {
                ViewData["AdminInfo"] = "请输入用户名密码！";
            }
            else
            {
                SysAdmin objAdmin = new SysAdmin()
                {
                    LoginId = Request.Params["loginId"].ToString(),
                    LoginPwd = Request.Params["loginPwd"].ToString()
                };
                objAdmin = new SysAdminManager().AdminLogin(objAdmin);
                if (objAdmin != null)
                {
                    ViewData["AdminInfo"] = objAdmin.AdminName;
                }
                else
                {
                    ViewData["AdminInfo"] = null;
                }
            }
            return View();
        }
    }
}

View Code

 

MVC - Views - SysAdmin reference code:

AdminLogin.cshtml：

@{
    Layout = null;
}

<!DOCTYPE html>

<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>AdminLogin</title>
</head>
<body>
    <div> 
        <form action="/SysAdmin/AdminLogin" method="post">
            用户名:<input type="text" name="
            Password:/>"loginId<input type="text" name="loginPwd" />
            <input type="submit" value="登录" />
        </form>
        @ViewData["AdminInfo"]
    </div>
</body>
</html>

View Code