How to create a three tier application?

Question

I want to create a website---Online Examination System in asp.net how can i create a three tier application for it??

Shivanand Arur · Answer

Hello Punita... A 3 Tier Architecture basically divides the project into 3 parts... 1. DAL(Data Access Layer) - here you will contain code which connects to the Data Source(Database). 2. BOL(Business Object Layer) - here you will contain the logic where you will interact with the DAL and get values in some methods. 3. UI Layer(User Interface Layer) - This layer will basically contain all the aspx pages and the logic for that particular page. When you send a request from a UI Layer it goes to the BOL layer which further interacts with the DAL Layer and then the DAL layer sends your value to the BOL layer which inturn returns it to the UI Layer. Example: Suppose your DAL has a Class called ClsConnection.cs ClsConnection.cs: using System; using System.Data; using System.Configuration; using System.Data.SqlClient; public class ClsConnection { public static int QueryExecution(commandtext) { SqlConnection con = new SqlConnection(Connection String); SqlCommand cmd = new SqlCOmmand(commandtext con); int value = cmd.ExecuteNonQuery(); return value; } } Suppose your BOL has a Class called GetIntValues.cs GetIntValues.cs using System; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using YourSolutionName.DAL; public class GetIntValues { public static int getValues() { int TotalValues = ClsConnection.QueryExecution(Select count(*) from TableName); return TotalValues; } } Suppose your UI Layer has a page called ShowIntValues.aspx So in the Code file you can show the value something like this... using System; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using YourSolutionName.BOL; protected void btnLogin_Click(object sender EventArgs e) { lblValue.Text = Convert.ToString(GetIntValues.getValues()); } In your case you can do the same thing... like you can add the database interaction code like creating the connection object command object here in a DAL. You can add some logic like to accepting the parameters calling DAL Methods in this BOL. And final in the UI Layer you can create your aspx pages which will contain its own specific logic according to your requirement. HOPE THIS HELPS YOU!!! PLEASE FEEL FREE TO ASK QUESTIONS IF YOU HAVE ANY DOUBTS PLEASE MARK THE ANSWER AS ACCEPTED IF IT HELPED YOU!!

Satyapriya Nayak · Answer

Hi Punita Please refer the below links http://www.c-sharpcorner.com/uploadfile/gowth/two-tier-and-three-tier-architecture-with-example/ http://www.aspdotnet-suresh.com/2010/05/introduction-to-3-tier-architecture-in_17.html http://dotnetslackers.com/articles/aspnet/3-Tier-Architecture-Examples.aspx http://1000projects.org/online-examination-system-project-in-asp-net.html Thanks

Prathap Kumar · Answer

Hi  Refer the following links it will help u http://www.dotnetfunda.com/articles/article71.aspx http://www.aspdotnet-suresh.com/2010/05/introduction-to-3-tier-architecture-in_17.html http://www.codeproject.com/Questions/401507/ASP-Net-3-Tier-architecture