set range using string variable for column letter - excel

Question

I'd like to know how to write this range changing "G" to a string variable strColumn.
This is the code I want to change:
Dim lastRowElemento As Integer
lastRowElemento = Cells(Rows.Count, "G").End(xlUp).Row
Set rngElemento = ws.Range("G2:G" & lastRowElemento)

Answer 1

Applying OP's method, try this:
Sub TEST()
Dim ws As Worksheet, Rng As Range, sCol As String
sCol = "G"
Set ws = ThisWorkbook.Sheets("TEST") 'change as required
With ws.Columns(sCol)
Set Rng = Range(.Cells(2), .Cells(.Rows.Count).End(xlUp))
End With
End Sub

Answer 2

Reference a 'Non-Empty' Column Range
There are actually two requirements:
ColumnString = G (I prefer string since e.g. XFD are letters)
FirstRow = 2
If you put them together, you get G2 (think one, instead of two variables).
Since using the Find method is more reliable than using the End property in finding the bottom-most (last) non-empty cell in a column, I used it to write the RefColumn function which in your case can be utilized in the following way:
Set rngElemento = RefColumn(ws.Range("G2"))
I'll leave it up to you if you're going to test if there is data (usually you know there is), but I prefer to keep at least a 'simplified' test in the code:
If rngElemento is Nothing Then Exit Sub ' no data
' Continue...
The Code
Option Explicit
Sub RefColumnTEST()
Dim wb As Workbook: Set wb = ThisWorkbook ' workbook containing this code
Dim ws As Worksheet: Set ws = wb.Worksheets("Sheet1")
Dim rg As Range: Set rg = RefColumn(ws.Range("G2"))
If rg Is Nothing Then ' the range 'G2:G1048576' is empty
MsgBox "No data.", vbCritical
Else
MsgBox rg.Address(0, 0), vbInformation
End If
End Sub
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Purpose: Creates a reference to the one-column range from the first cell
' of a range ('FirstCell') to the bottom-most non-empty cell
' of the first cell's worksheet column.
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function RefColumn( _
ByVal FirstCell As Range) _
As Range
If FirstCell Is Nothing Then Exit Function
With FirstCell.Cells(1)
Dim lCell As Range
Set lCell = .Resize(.Worksheet.Rows.Count - .Row + 1) _
.Find("*", , xlFormulas, , , xlPrevious)
If lCell Is Nothing Then Exit Function
Set RefColumn = .Resize(lCell.Row - .Row + 1)
End With
End Function
Meeting Your Requirements
Similarly to my preferred way, you could use the RefData function:
Function RefData( _
ByVal ws As Worksheet, _
ByVal ColumnIndex As Variant) _
As Range
On Error GoTo ClearError
With ws.Columns(ColumnIndex).Resize(ws.Rows.Count - 1).Offset(1)
Set RefData = _
.Resize(.Find("*", , xlFormulas, , , xlPrevious).Row - 1)
End With
ProcExit:
Exit Function
ClearError:
Resume ProcExit
End Function
which you can utilize in the following way:
Set rngElemento = RefData(ws, "G")
Set rngElemento = RefData(ws, 7)
' or:
Const strColumn As String = "G"
Set rngElemento = RefData(ws, strColumn)