hi guys,
in the past i had to struggle to get my solution organized so that i would not have troubles of maintenance. I came across a lot of models and methods but I was not really fully satisfied. Hoever, I decided to go for separation of layers of my solution into projects namely, myweb(the site), BLL (Business Logic Layer) and DAL (Data Access Layer).

However, I ran into problem passing data between BLL and DAL because there are times i need to pass complex data and I wanted to avoid passing unreasonable no of parameters. For instance, say i want to update a student data that has 60 fields through DAL from BLL, i needed to pass the 60 parameters to DAL from BLL. I guess this is not a best practice. Note that I could not pass BLL objects to DAL as this will result in circular reference.

So, I introduced another layer to my solution called PRL (Presentation Layer). This layer forms the base layer for the BLL and DAL and contains the basic abstract classes that I would pass between DAL and BLL. As a matter of separation principle I made sure that PRL objects do not contain any methods. I make BLL objects inherit from these objects and therefor can pass BLL objects to DAL without hassles. finito.


Here are my sample codes

PRL (VB)
Public MustInherit Class Account
Private _accountNumber As String
Private _accountName As String
Private _balance As Double

Public Property AccountNumber() As String
Get
Return _accountNumber
End Get
Set(ByVal value As String)
_accountNumber = value
End Set
End Property
Public Property AccountName() As String
Get
Return _accountName
End Get
Set(ByVal value As String)
_accountName = value
End Set
End Property
Public Property Balance() As Double
Get
Return _balance
End Get
Set(ByVal value As Double)
_balance = value
End Set
End Property

End Class

DAL (VB)
Public Class InsertAccount
Public Function Update(ByVal account As Presenters.Account) As Boolean

'//call stored procedure or something and return success or otherwise
Return True

End Function


End Class

BLL (C#)
public class Account : Presenters.Account
{
public bool Update()
{
DAL.InsertAccount ia = new DAL.InsertAccount();
return ia.Update(this);
}
}


SampleSite (C#)
protected void Page_Load(object sender, EventArgs e)
{
BLL.Account acct = new BLL.Account();
acct.AccountName = "Magaji";
acct.AccountNumber = "12346578";
acct.Balance = 123311123321;

if (acct.Update()) this.TextBox1.Text = "Updated";
else this.TextBox1.Text = "Failed";

}

Please, never mind about language mixing. I also use it to relay that .NET solution can contain more language.

Please enjoy.

Good luck.