Loop sheets and transfer data - excel

Question

My brain is fried and this is easy points for the usual suspects. div is an array holding sheet names. I am looping through sheets in a master book and if one of the master sheets match one of the sheets in the div array, I want to transfer some data from master sheet to a sheet in thisworkbook.
In the event the sheet does not exist in thisworkbook, add one and name it after the master sheet. What's the most efficient way to do this? I feel like nested loops is a bad idea -_- A collection perhaps?
For i = 0 To UBound(div())
For Each s In book.Worksheets
wsName = Left(s.Name, 5)
If div(i) = wsName Then
If wsExists(wsName) Then
Set ws = ThisWorkbook.Worksheets(wsName)
Exit For
'Debug.Print "true " & ws.name
Else
Set ws = ThisWorkbook.Worksheets.Add
ws.Name = Left(s.Name, 5)
'Debug.Print "false " & ws.name
End If
end if
Next
With ws
.Columns(Start).Resize(, 2).Value = s.Columns("A:B").Value
.Columns(Start + label).Resize(, cols).Value = s.Columns(Start + label).Resize(, cols).Value
End With
Next
Do I even need to check if sheet exists? Code stolen from Tim.
Function wsExists(sName As String) As Boolean
Dim sht As Worksheet
On Error Resume Next
Set sht = ThisWorkbook.Sheets(sName)
On Error GoTo 0
wsExists = Not sht Is Nothing
End Function
Edit: I am calling the loop from a separate routine.
Call drop(thisWB, thisRange, ccArr)
where ccArr is
Dim ccArr() As Variant
ccArr = Array("30500", "30510", "30515", "30530", "30600", "30900", "40500")
The routine where above loop resides opens with
Sub drop(book As Workbook, cols As Integer, div As Variant, Optional startCol As Integer)
but I am getting a byref error trying to pass the array ;_;

Answer 1

Your nested loop is superfluous. You can check the sheet name from div directly against the workbook you want to check it against, then add it if needed.
See the code below, which also addresses the concerns in the edits to your OP. I modified the wsExists function to include a set reference to a particular workbook, which I think makes it more dynamic.
'assumes thisWB and thisRange set above
Dim ccArr() As String, sList As String
sList = "30500,30510,30515,30530,30600,30900,40500"
ccArr = Split(sList, ",")
drop thisWB, thisRange, ccArr 'assumes thisWb and thisRange are set already
' rest of code
'==================================================
Sub drop(book As Workbook, cols As Integer, div() As String, Optional startCol as Integer)
For i = 0 To UBound(div())
If wsExists(ThisWorkbook, div(i)) Then
Set ws = ThisWorkbook.Worksheets(div(i))
Exit For
'Debug.Print "true " & ws.name
Else
Set ws = ThisWorkbook.Worksheets.Add
ws.Name = div(i)
End If
'i think you need this here, otherwise, it will only work on the last worksheet in your loop
With ws
Dim s As Worksheet
Set s = book.Sheets(div(i))
.Columns(Start).Resize(, 2).Value = s.Columns("A:B").Value
.Columns(Start + Label).Resize(, cols).Value = s.Columns(Start + Label).Resize(, cols).Value
End With
Next
End Sub
Function wsExists(wb As Workbook, sName As String) As Boolean
Dim sht As Worksheet
On Error Resume Next
Set sht = wb.Sheets(sName)
On Error GoTo 0
wsExists = Not sht Is Nothing
End Function

Answer 2

Related to the re-sizing code:
This statement ws.Columns(1).Resize(, 2) translates to "2 million+ rows from column 1 and 2"
The solution you found works well but it's not dynamic (hard-coded last row)
This is how I'd setup the copy of columns:
Option Explicit
Public Sub copyCols()
Dim ws1 As Worksheet, ws2 As Worksheet, rng1 As Range, rng2 As Range
Dim cols As Long, lr As Long
Dim col1 As Long 'renamed from "Start" (VBA keyword - property)
Dim lbl As Long 'renamed from "label" (VBA keyword - Control object)
Set ws1 = Sheet1 'ws
Set ws2 = Sheet2 'book.Worksheets(wsName & "-F")
col1 = 1
cols = 2
lbl = 1
lr = ws2.Cells(ws2.UsedRange.Row + ws2.UsedRange.Rows.Count, "A").End(xlUp).Row
Set rng1 = ws1.Range(ws1.Cells(1, col1), ws1.Cells(lr, col1 + 1))
Set rng2 = ws2.Range("A1:B" & lr)
rng1.Value2 = rng2.Value2
Set rng1 = ws1.Range(ws1.Cells(1, col1 + lbl), ws1.Cells(lr, col1 + lbl + cols))
Set rng2 = ws2.Range(ws2.Cells(1, col1 + lbl), ws2.Cells(lr, col1 + lbl + cols))
rng1.Value2 = rng2.Value2
End Sub