Excel - Open Workbooks given names - vba

Question

I have the below code.
Very simply it asks the user to select multiple excel workbooks and then will copy and paste data from those workbooks to the current work book.
1.
I would like to add the functionality, whereby instead of the user selecting the excel workbooks. The excel workbooks will be selected in that their names are listed on the current excel sheet.
For example - Select excel workbooks in specified folder whose names are listed in A1:A5.
I would like to perform automatic processing on the data before it is copied into the current work book.
For example if workbook name = 100.xlsx then multiply selection by 15.
See my current code
Sub SUM_BalanceSheet()
Application.ScreenUpdating = False
'FileNames is array of file names, file is for loop, wb is for the open file within loop
'PasteSheet is the sheet where we'll paste all this information
'lastCol will find the last column of PasteSheet, where we want to paste our values
Dim FileNames
Dim file
Dim wb As Workbook
Dim PasteSheet As Worksheet
Dim lastCol As Long
Set PasteSheet = ActiveSheet
lastCol = PasteSheet.Cells(1, Columns.Count).End(xlToLeft).Column
'Build the array of FileNames to pull data from
FileNames = Application.GetOpenFilename(filefilter:="Excel Files (*.xlsx), *.xlsx", MultiSelect:=True)
'If user clicks cancel, exit sub rather than throw an error
If Not IsArray(FileNames) Then Exit Sub
'Loop through selected files, put file name in row 1, paste P18:P22 as values
'below each file's filename. Paste in successive columns
For Each file In FileNames
Set wb = Workbooks.Open(file, UpdateLinks:=0)
PasteSheet.Cells(1, lastCol + 1) = wb.Name
wb.Sheets("Page 1").Range("L14:L98").Copy
PasteSheet.Cells(2, lastCol + 1).PasteSpecial Paste:=xlPasteValues
wb.Close SaveChanges:=False
lastCol = lastCol + 1
Next
'If it was a blank sheet then data will start pasting in column B, and we don't
'want a blank column A, so delete it if it's blank
If Cells(1, 1) = "" Then Cells(1, 1).EntireColumn.Delete shift:=xlLeft
Application.CutCopyMode = False
Application.ScreenUpdating = True
End Sub

Answer 1

This is a frame that needs fine-tuning, but you can get the idea:
Dim i&, wbName$
Dim rng As Excel.Range
Dim wb, wb1 As Excel.Workbook
Set wb = Application.ThisWorkbook
Set rng = wb.Sheets("Sheet1").Range("A1")
For i = 0 To 14
wbName = CStr(rng.Offset(i, 0).Value)
On Error Resume Next 'Disable error handling. We will check whether wb is nothing later
wb1 = Application.Workbooks.Open(wbName, False)
On Error GoTo ErrorHandler
If Not IsNothing(wb1) Then
'Copy-paste here
If wb1.Name = "100" Then 'any condition(s)
'Multiply, divide, or whatever
End If
End If
Next
ErrorHandler:
MsgBox "Error " & Err.Description
'Add additional error handling
Try not to use ActiveSheet and ActiveWorkbook without absolute need. Use ThisWorkbook, dedicated Workbook object, and named sheet Workbook.Sheets("Name") or Workbook.Sheets(index) instead.
Alternatively instead of disabling error checking you can do it and fail if a file is missing.