Dynamic data structures in VBA - excel

Question

Currently I am trying to improve the performance of my VBA program, because it takes forever to perform some table operations.
During the programs runtime I am trying to store data in worksheets, but the write-operations take for ever and I would like to store this data dynamically instead of writing it into a worksheet to reduce the time it needs to run.
I was thinking about using arrays instead of the worksheets to store the data but I am not quite sure whether this will work because I do not know how many rows/columns my table exactly has.
Here my code, any help is appreciated!
Public row As Long
Public rowMax As Long
Public startRow As Integer
Public materialType As String
Public filter As String
Public col As Integer
Public colMax As Integer
Public isUsed As Boolean
Public a As Integer
Sub bestimmeObFelderGenutzt()
Debug.Print ("bestimmeObFelderGenutzt:begin" & " " & Now())
With Sheets("Sheet1")
filter = "I"
startRow = 2
rowMax = Sheets("Sheet1").Cells(.Rows.Count, "F").End(xlUp).row
colMax = Sheets("Sheet1").Cells(1, .Columns.Count).End(xlToLeft).Column
materialType = Sheets("Sheet1").Range(filter & startRow).Value
Dim ws As Worksheet
Set ws = ThisWorkbook.Sheets.Add(After:= _
ThisWorkbook.Sheets(ThisWorkbook.Sheets.Count))
ws.Name = "Nutzung"
For col = 1 To colMax
Sheets("Nutzung").Cells(1, col + 2).Value = Sheets("Sheet1").Cells(1, col).Value
Next col
For row = 2 To rowMax
Sheets("Nutzung").Range("A" & row).Value = Sheets("Sheet1").Range("A" & row).Value
Sheets("Nutzung").Range("B" & row).Value = Sheets("Sheet1").Range("I" & row).Value
For col = 1 To colMax
If IsEmpty(Sheets("Sheet1").Cells(row, col)) = False Then
isUsed = True
Sheets("Nutzung").Cells(row, col + 2).Value = 1
Else:
Sheets("Nutzung").Cells(row, col + 2).Value = 0
End If
Next col
Next row
End With
Debug.Print ("bestimmeObFelderGenutzt:end" & " " & Now())
End Sub
Sub findeUngenutzteSpalten(ByVal materialType As String, pos As Integer)
Debug.Print ("findeUngenutzteSpalten:begin" & " " & materialType & " " & Now())
With Sheets(materialType)
rowMax = Sheets(materialType).Cells(.Rows.Count, "F").End(xlUp).row
colMax = Sheets(materialType).Cells(1, .Columns.Count).End(xlToLeft).Column
Sheets("Auswertung").Cells(1, 1).Value = "Spaltenüberschrift:"
Dim a As Integer
For a = 1 To colMax
Sheets("Auswertung").Cells(a + 1, 1).Value = Sheets("Sheet1").Cells(1, a).Value
Next a
Sheets("Auswertung").Cells(1, pos + 1).Value = materialType
For col = 3 To colMax
For row = 2 To rowMax
If Sheets(materialType).Cells(row, col).Value = 1 Then
Sheets("Auswertung").Cells(col - 1, pos + 1).Value = "Ja"
GoTo WeiterCol
Else:
If row = rowMax Then
Sheets("Auswertung").Cells(col - 1, pos + 1).Value = "Nein"
Else:
GoTo WeiterRow
End If
End If
WeiterRow:
Next row
WeiterCol:
Next col
End With
Debug.Print ("findeUngenutzteSpalten:end" & " " & materialType & " " & Now())
End Sub
Sub kopiereZeilen(ByVal materialType As String)
Debug.Print ("kopiereZeilen:begin" & " " & materialType & " " & Now())
With Sheets("Nutzung")
rowMax = Sheets("Nutzung").Cells(.Rows.Count, "F").End(xlUp).row
Dim ws As Worksheet
Set ws = ThisWorkbook.Sheets.Add(After:= _
ThisWorkbook.Sheets(ThisWorkbook.Sheets.Count))
ws.Name = materialType
Sheets("Nutzung").Cells(1, 1).EntireRow.Copy Sheets(materialType).Cells(1, 1)
Dim unusedRow As Long
For row = 2 To rowMax
unusedRow = Sheets(materialType).Cells.SpecialCells(xlCellTypeLastCell).Offset(1, 0).row
If Sheets("Nutzung").Cells(row, 2).Value = materialType Then
Sheets("Nutzung").Cells(row, 2).EntireRow.Copy Sheets(materialType).Cells(unusedRow, 1)
End If
Next row
End With
Debug.Print ("kopiereZeilen:end" & " " & materialType & " " & Now())
End Sub
Sub allesZusammen()
Debug.Print ("Hauptaufruf:begin" & " " & Now())
Dim types(10) As String
Dim element As Variant
Dim pos As Integer
bestimmeObFelderGenutzt
types(0) = "A"
types(1) = "B"
types(2) = "C"
types(3) = "D"
types(4) = "E"
types(5) = "F"
types(6) = "G"
types(7) = "H"
types(8) = "I"
types(9) = "J"
types(10) = "K"
Dim ws As Worksheet
Set ws = ThisWorkbook.Sheets.Add(After:= _
ThisWorkbook.Sheets(ThisWorkbook.Sheets.Count))
ws.Name = "Auswertung"
For Each element In types
kopiereZeilen (element)
pos = Application.Match(element, types, False)
findeUngenutzteSpalten element, pos
Next element
Debug.Print ("Hauptaufruf:end" & " " & Now())
End Sub

Answer 1

You can declare dynamic arrays. The general syntax is:
Dim Values() As Long
To use the array, you must first re-dimension it to the size you want. For example this declares a two-dimensional array of 3 x 5 values (zero based):
ReDim Values(2, 4)
If you want to size based on variables then use something like:
ReDim Values(myrowsize, mycolumnsize)
You can grow (or shrink) the array dynamically by using this syntax:
ReDim Preserve Values(2, mynewsize)
Note, that you can only re-dimension the last index of the array. So this is not allowed:
ReDim Preserve Values(mynewsize, 4)
But this is probably ok in your case, as you have a fixed number of columns.
It is perfectly ok to declare the dynamic array as a UDT. For example:
Type UDTInfo
valueA As Long
valueB As Long
End Type
Sub test()
Dim Values() As UDTInfo
ReDim Values(2, 4)
ReDim Preserve Values(2, 5)
End Sub
You can access the array in the normal way:
x = Values(1, 2)
You can copy one dynamic array to another directly, as long as the types and number of dimensions match (size doesn't matter):
Dim Values() As Integer
Dim Results() As Integer
Results = Values
And lastly, you can pass dynamic arrays to and from functions in the following way:
Function SomeFunc(ByRef Values() As Long) As Long()
Dim ReturnValues() As Long
ReturnValues = Values
SomeFunc = ReturnValues
End Function
Note, you only pass dynamic arrays ByRef but not ByVal.