How do I copy the functionality of Range.Cells in my own class? - vba

Question

I am trying to emulate the Range.Cells(row, col) property in my own class. My .Cells property does update the specified cell correctly.
The problem, however, is that as I'm typing d.Cells(1, 3) =, after the equals sign intellisense will suggest "Cells(row As Long, col) as Range". I'm not sure if this will cause problems for me down the track.
The Cells property is defined like this:
Property Get Cells(row As Long, col As Variant) As Range
' Get the column number for the requested cell
Dim c As Long
If IsNumeric(col) Then
' ensure it is an int
c = CInt(col)
ElseIf VarType(col) = vbString Then
' Get column number from the header name
c = Me.Column(CStr(col))
Else
' Otherwise, variant type is not supported
Exit Property
End If
' Return the requested Cell if column number is valid
If c > 0 And c <= pHeaderRange.Columns.Count Then
Set Cells = pHeaderRange.CurrentRegion.Cells(1 + row, c)
' the row is +1 because pHeaderRange.CurrentRegion also returns
' the header row
End If
End Property
I have also tried this:
Public Property Get Cells(row As Long, col As Variant) As Range
' same code as above
End Property
Public Property Set Cells(v As Variant)
' some code here
End Property
But I get the message: "Compile Error: Definitions of property procedures for same property are inconsistent, or property procedure has an optional parameter a ParamArray, or an invalid Set final parameter."
I think I get the compile error because of parameters I have included in this line Property Get Cells(row As Long, col As Variant) As Range. But I need these parameters to select the cell.
What is the correct way to define the .Cells property in a user defined class so that it works the same way as Range.Cells?
Full code is:
Option Explicit
Private pHeaderRange As Range
'
' Sets the Range of the header row.
'
' -r Range The header row is expected to the in the CurrentRegion of r.
'
Property Let Header(location As Range)
' if range is empty, only the top, left cell will be selected
Dim r As Range
Set r = location.CurrentRegion
' if top row is blank, then remove top row from the range
If WorksheetFunction.CountA(r.Rows(1)) = 0 Then
' dont (and cant) resize unless there are multiple rows in the range
If r.Rows.Count > 1 Then
Set r = r.Resize(r.Rows.Count - 1, r.Columns.Count).Offset(1, 0) ' resizes and repositions range
Else
' the is no header, only a blank cell
Set pHeaderRange = r
Exit Property
End If
End If
' find the starting column of the header row
Dim startCell As Range
Dim endCell As Range
Set startCell = r.Cells(1, 1)
If IsEmpty(startCell) Then
' if startCell is empty, look for header to the right
Set startCell = r.End(xlToRight)
ElseIf IsEmpty(startCell.Offset(0, -1)) Then
' if cell to the left is empty, we have already found the start of the header
Else
' otherwise move to left to find the start
Set startCell = startCell.End(xlToLeft)
End If
' find the last column of the header row
If IsEmpty(startCell.Cells(1, 2)) Then
' if cell to the right is empty, header row only contains one cell
Set endCell = startCell
Else
' otherwise move to right to find the end
Set endCell = startCell.End(xlToRight)
End If
' store the header range
Set pHeaderRange = Range(startCell, endCell)
' debug
pHeaderRange.Select
End Property
'
'
Public Property Get Cells(row As Long, col As Variant) As Range
' Get the column number for the requested cell
Dim c As Long
If IsNumeric(col) Then
' change to int
c = CInt(col)
ElseIf VarType(col) = vbString Then
' Get column by header name
c = Me.Column(CStr(col))
Else
' Otherwise, variant type is not supported
Exit Property
End If
' Return the requested Cell if column number is valid
If c > 0 And c <= pHeaderRange.Columns.Count Then
Set Cells = pHeaderRange.CurrentRegion.Cells(1 + row, c) ' the row is +1 because CurrentRegion also returns the header row
End If
End Property
Public Property Set Cells(v As Range)
' some code here
End Property
'
' Returns the entire column range of the header that matches the index.
'
' -name String The header name to find
'
Public Property Get Column(name As String) As Long
' Find header
On Error Resume Next ' continue even if name is not found (ie Find returns an error)
Dim r As Range
Set r = pHeaderRange.Find(name)
' return column number
Column = r.Column - pHeaderRange.Column + 1
End Property

Answer 1

http://msdn.microsoft.com/en-us/library/gg251357.aspx
The parameters for Property Get, Property Let, and Property Set procedures for the same property must match exactly, except that the Property Let has one extra parameter, whose type must match the return type of the corresponding Property Get...
The problem is that you have arguments in your Get that aren't in your Set. So this would work
Public Property Get Cells(lrow As Long, vcol As Variant) As Range
End Property
Public Property Set Cells(lrow As Long, vcol As Variant, v As Range)
End Property
Except that it makes no sense (which you already know). The reason Cells works in the Excel object model is that it's a read-only property (there's a Get, but no Let or Set). The Cells property returns a Range object, but you can't set Cells. I'm not sure what you're trying to accomplish with your Set statement, but perhaps you don't need it. You don't seem to have any module level variables to store it.

Answer 2

If I understand well your question, maybe you could try:
Public Property Set Cells(row As Long, col As Variant) As Range
'code to set the class
End Property
See some tips on this thread: Set property of vba class with object reference