Code wont loop through sheets as well as rows - vba

Question

I am trying to write code to loop through all sheets in a workbook, apart from 1, and add a column which is a concatenation of 3 others. This seems to loop through all the rows for one worksheet, but not the others in the book
Sub addConcats()
Dim sh As Worksheet
Dim rw As Range
Dim RowCount As Integer
'Run through worksheets
Dim x As Long
Sheet1.Select
For x = 2 To ThisWorkbook.Sheets.Count
If Sheets(x).Name <> "VAT Transaction Report" Then Sheets(x).Select
Replace:=False
Dim LastRow As Long
LastRow = ActiveSheet.UsedRange.Row - 1 + ActiveSheet.UsedRange.Rows.Count
For y = 2 To LastRow
'Concat
ActiveSheet.Cells(y, 20).Value = ActiveSheet.Cells(y, 7).Value &
ActiveSheet.Cells(y, 9).Value & ActiveSheet.Cells(y, 12).Value
Next y
Next x
End Sub

Answer 1

No need to select each worksheet for this, or run with x and y.
Sub addConcats()
Dim sh As Worksheet
Dim LastRow As Long
For Each sh in ThisWorkbook.Worksheets
If sh.Name <> "VAT Transaction Report" Then
LastRow = sh.Cells(sh.Rows.Count, 1).End(xlUp)
For y = 2 To LastRow
'Concat
sh.Cells(y, 20).Value = sh.Cells(y, 7).Value & sh.Cells(y, 9).Value & sh.Cells(y, 12).Value
Next y
End If
Next
End Sub

Answer 2

Try the code below, for your For loop to take into consideration the Sheets(x) you are trying to update:
Dim LastRow As Long
For x = 2 To ThisWorkbook.Sheets.Count
If Sheets(x).Name <> "VAT Transaction Report" Then
With Sheets(x)
LastRow = .UsedRange.Row - 1 + .UsedRange.Rows.Count
For y = 2 To LastRow
'Concat
.Cells(y, 20).Value = .Cells(y, 7).Value & .Cells(y, 9).Value & .Cells(y, 12).Value
Next y
End With
End If
Next x

Answer 3

The problem is that you select a sheet, but do not use Sheet.Activate. Next you use ActiveSheet. It is better to avoid selecting sheets altogether and just work against a Worksheet object (sh variable)
Try the following:
Sub addConcats()
Dim sh As Worksheet
Dim x As Integer
Dim y As Integer
Dim LastRow As Long
For x = 1 To ThisWorkbook.Sheets.Count
Set sh = Sheets(x)
If sh.Name <> "VAT Transaction Report" Then
LastRow = sh.UsedRange.Rows.Count
For y = 2 To LastRow
'Concat
sh.Cells(y, 20).Value = sh.Cells(y, 7).Value & sh.Cells(y, 9).Value & sh.Cells(y, 12).Value
Next y
End If
Next x
End Sub