VB6 Simple ORM Idea

Just a simple idea of how to create dynamic classes using vb6 to perform access and fetch data stored in a database and little more.

⚠️ This is a working in progress

Usage

Dim objArray As Variant
Dim objClient As clsClient
Dim i As Long
Dim params As New clsParams

params.Add "name", "%mary%", "ilike"
params.Add "id", 6
objArray = DataBaseSelect(C_clsClient, params)
If HasValues(objArray) Then
    Debug.Print "Count:" & UBound(objArray)
    For i = 1 To UBound(objArray)
      Set objClient = objArray(i)
       Debug.Print "ID:" & objClient.ID
       Debug.Print "Name:" & objClient.Name
       Debug.Print "Age:" & objClient.Age
       Debug.Print "Email:" & objClient.Email
       Debug.Print "Errors:" &  objClient.AsIBaseClass.CheckErrors
       Debug.Print ""
       Debug.Print ""
    Next i
End If

'Example of execution
Count:1
ID:6
Name:Mary
Age:31
Email:mary@example.com
Errors:Age value is invalid

Classes setup

Databases classes must implement IBaseClass

In Class_Initialize all properties and annotations must be added File:clsClient.bas

Implements IBaseClass
Private namedClass As NamedPropertiesClass

Public Sub Class_Initialize()
    Set namedClass = New NamedPropertiesClass
    namedClass.Add("id", PrimaryKey, True).AddAnnotation AutoIncrement, True
    namedClass.Add "Name"
    namedClass.Add "Age", Validator, V_AgeValidator
    namedClass.Add "Email"
End Sub

Private Function IBaseClass_GetTableName() As String
        IBaseClass_GetTableName = "client"
End Function

Private Function IBaseClass_Props() As NamedPropertiesClass
      Set IBaseClass_Props = namedClass
End Function

Properties implementation

Public Property Let ID(ByVal value As Variant)
    namedClass.PropertyByName("ID") = value
End Property

Public Property Get ID() As Variant
    ID = namedClass.PropertyByName("ID")
End Property

Validators

All Validator must be in clsValidator and in Validator_Constants

File:clsValidator.bas

Public Function Validator_Age(value As Variant) As Boolean
    Validator_Age = (value >= 40)
End Function

File:Validator_Constants.bas

Public Const V_AgeValidator As String = "Validator_Age"

To-do	Status
Dynamic properties	✅
Select with simple text	✅
Select with parametrized query	✅
annotations support	✅
create routine
update routine
insert routine	working
transaction support
external validators support	✅

License: GNU General Public License v3.0