Most of the projects in .NET are developed
using tier / layer architecture. Though tier and layer have different meaning,
but for all .NET beginners I am using same term.
Below is typical diagram of 3 tier
architecture.
- Presentation
Layer: It’s a User Interface Layer (UIL) where users are interacting
with an application. It also contains additional application logic. This
layer may be ASP.NET, windows or mobile application. This layer interacts
with middle layer. It never directly access data layer.
2. Business Layer: It’s a Business Logic Layer
(BLL) which communicates both to Presentation layer or Data Layer.
3. Data Layer: It’s a Data Access Logic Layer
(DAL) which interacting with database.
Steps to create in Visual Studio using C#
- Create one window / web
project.
- Right click on your
solution, Add one new project as shown below
- Select one class library
project, specify its name as “DataAccessLayer”, as shown below
- Similarly create another
class library name as “BusinessLogicLayer”
- Create classes in DataAccessLayer
for StudentInfo table as shown below
|
using System;
using System.Data;
using System.Collections.Generic;
using System.Text;
namespace DataAccessLayer
{
class StudentInfo
{
public
DataTable LoadAll()
{
//Write
code to load all the records of studentinfo Table
DataTable
objDataTable = new DataTable();
return
objDataTable;
}
//Write
rest of the code for each SP - Insert, Update, delete
}
}
|
- Build DataAccessLayer
Project.
- Add the reference of DataAccessLayer
in BusinessLogicLayer project as shown below
- Try to access the DataAccessLayer’s
StudentInfoDAL class in BusinessLogicLayer as shown below
|
using System;
using System.Data;
using System.Collections.Generic;
using System.Text;
using DataAccessLayer;
namespace BusinessLogicLayer
{
public class StudentInfoBLL
{
/// <summary>
/// Call the StudentInfoDAL class of DataAccessLayer
/// </summary>
/// <returns></returns>
public
DataTable LoadAll()
{
StudentInfoDAL
objStudentInfoDAL = new StudentInfoDAL();
return
objStudentInfoDAL.LoadAll();
}
//Write
rest of the code to call the Insert, Update, delete method of StudentInfoDAL
}
}
|
- Build BusinessLogicLayer
Project.
- Similarly Add the
reference of BusinessLogicLayer in your window / web project.
- Try to access the
BusinessLogicLayer’s StudentInfoBLL class.
|
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using BusinessLogicLayer;
namespace _3TierDemo
{
public partial class _Default : System.Web.UI.Page
{
protected
void Page_Load(object
sender, EventArgs e)
{
if
(!Page.IsPostBack)
{
BindStudentInfoData();
}
}
public
void BindStudentInfoData()
{
StudentInfoBLL
objStudentInfoBLL = new StudentInfoBLL();
DataTable
objDataTable = objStudentInfoBLL.LoadAll();
GridView1.DataSource =
objDataTable;
GridView1.DataBind();
}
}
}
|
Finally your 3-Tier application look like.
Hope this is helpful. Please leave your comments
for any help / suggestion.
