Implement same logic for diffrent objects as T - vb.net

Question

I suppose to use T but i am not sure how do it in proper way.
Let's consider following example.
Base class:
Public Class HtmlBase
Implements IGetInformation
Public Overridable Function IsExist() As Boolean Implements IGetInformation.IsExist
Throw New NotImplementedException()
End Function
Public Overridable Function GetIdByName(pName As String) As Integer Implements IGetInformation.GetIdByName
Throw New NotImplementedException()
End Function
End Class
Example classes which inherit from base class:
Public Class HtmlSubSection
Inherits HtmlBase
'--sometimes i have to overload to add additioinal parameter
Public Overloads Function isExist(subsection As String) As Boolean
Dim dlsubkategorie As New DataLayer.DALSubSection
Return dlsubkategorie.CheckIfSubSectionExist(subsection)
End Function
Public Overrides Function GetIdByName(subsectionName As String) As Integer
Dim dlget As New DataLayer.DALSubSection
Return dlget.GetSubSectionIdByName(subsectionName)
End Function
End Class
Public Class HtmlSection
Inherits HtmlBase
'sometime i have to overload to add additioinal parameter
Public Overloads Function IsExist(section As String) As Boolean
Dim dlsubkategorie As New DataLayer.DALSection
Return dlsubkategorie.CheckIfSectionExist(section)
End Function
Public Overrides Function GetIdByName(Name As String) As Integer
Dim dlsubkategorie As New DataLayer.DALSection
Return dlsubkategorie.GetSectionIdByName(Name)
End Function
End Class
As could be seen above two classes which inherits from base within their methods has same logic (sometimes i have to use additional parameter therefore overloads there, but are using diffrent DAL class to call. I would like to implement this logic in base class and for each just point to specific DAL. How to do that to not everytime in those classes write e.g:
Dim dlsubkategorie As New DataLayer.<DALSection>
Return dlsubkategorie.GetSectionIdByName(Name)
EDIT:
Htmlbase constructor's:
Sub New()
End Sub
Sub New(pId As Integer)
_Id = pId
End Sub
HtmlSubSection's constructors:
Sub New()
MyBase.New()
AvailableSentences = New List(Of HtmlSubSection_Sentence)
SelectedSentences = New List(Of HtmlSubSection_Sentence)
End Sub
Sub New(pId As Integer)
MyBase.New(pId)
End Sub
Sub New(pName As String)
_Name = pName
End Sub
Sub New(pId As Integer, pName As String)
MyBase.New(pId)
_Name = pName
End Sub
HtmlSection's constructors:
Sub New()
MyBase.New()
End Sub
Sub New(pId As Integer)
MyBase.New(pId)
End Sub
Sub New(pId As Integer, pName As String, pPosition As Integer)
MyBase.New(pId)
_Name = pName
_Position = pPosition
End Sub
Sub New(pName As String)
_Name = pName
End Sub
Sub New(pName As String, pPosition As Integer)
_Name = pName
_Position = pPosition
End Sub

Answer 1

You don´t need generic types here. Just use Interfaces, Sub Classing and Polymorphism correctly.
New Interface IDAL which is implemented by DAL classes to get rid of different method names which take same parameters and do the same:
Public Interface IDAL
Function CheckIfSectionExist(section As string) As Boolean
Function GetSectionIdByName(section As string) As Integer
End Interface
Public Class DALSection
Implements IDAL
Public Function CheckIfSectionExist(section As string) As Boolean Implements IDAL.CheckIfSectionExist
...
End Function
Public Function GetSectionIdByName(section As String) As Integer Implements IDAL.GetSectionIdByName
...
End Function
End Class
Public Class DALSubSection
Implements IDAL
Public Function CheckIfSubSectionExist(subSection As string) As Boolean Implements IDAL.CheckIfSectionExist
...
End Function
Public Function GetSubSectionIdByName(subSection As String) As Integer Implements IDAL.GetSectionIdByName
...
End Function
End Class
Base class changed to abstract and the constructor now takes IDAL parameter. Function can now be executed polymorphic. Added a isExists(string) function to avoid overloading:
Public MustInherit Class HtmlBase
Implements IGetInformation
Public Property DAL as DataLayer.IDAL
Protected Sub New(dal as DataLayer.IDAL)
Me.DAL = dal
End Sub
Public Overridable Function isExist() As Boolean Implements IGetInformation.isExist
Return True
End Function
Public Overridable Function isExist(section As String) As Boolean
Return DAL.CheckIfSectionExist(Section)
End Function
Public Overridable Function GetIdByName(pName As String) As Integer Implements IGetInformation.GetIdByName
Return DAL.GetSectionIdByName(pName)
End Function
End Class
Client classes only need to give correct DAL to base class:
Public Class HtmlSubSection
Inherits HtmlBase
Public Sub New()
MyBase.New(New DataLayer.DALSubSection)
End Sub
End Class
Public Class HtmlSection
Inherits HtmlBase
Public Sub New()
MyBase.New(New DataLayer.DALSection)
End Sub
End Class
Basically it would be ideal if IGetInformation had a isExist method with an optional string parameter. This would save one unneccessary method in HtmlBase.