VBA to duplicate large dataset using array - vba

Question

I have data on sheet A and want to duplicate it on sheet B. Because it is a lot of data, I do not want to use copy-paste. If I really simplify it, this is my code. My ranges change although I made it sort of fixed in this simplified code. I do not want to use something like range("A1:BBB100000") since my range will change. I get 1004 error "Application-defined or object-defined error". What am I doing wrong?
Dim origin(1 to 100000, 1 to 100000) as Variant
Dim dest(1 to 100000, 1 to 100000) as Variant
Set A=Worksheets("A")
Set B=Worksheets("B")
Vrow=100000
set origin=A.range(cells(1,1),cells(Vrow, Vrow))
set dest=B.range(cells(1,1),cells(Vrow, Vrow))
dest=origin

Answer 1

You don't need the array. Only generate an array if your actually going to do any calculations on it. If you just want to do value -> value then that's what you do (as shown below).
Remember to always declare all your variables as well.
Dim A As Worksheet, B As Worksheet, Vrow As Long
Set A = Worksheets("A")
Set B = Worksheets("B")
Vrow = 100000
B.Range(B.Cells(1, 1), B.Cells(Vrow, Vrow)).Value = A.Range(A.Cells(1, 1), A.Cells(Vrow, Vrow)).Value

Answer 2

Copy Range Values to Another Worksheet
Sub CopyValues()
Const sName As String = "A"
Const sFirstCellAddress As String = "A1"
Const dName As String = "B"
Const dFirstCellAddress As String = "A1"
Dim wb As Workbook: Set wb = ThisWorkbook ' workbook containing this code
Dim sws As Worksheet: Set sws = wb.Worksheets(sName)
Dim sfCell As Range: Set sfCell = sws.Range(sFirstCellAddress)
Dim srg As Range: Set srg = sfCell.CurrentRegion
Dim dws As Worksheet: Set dws = wb.Worksheets(dName)
Dim dfCell As Range: Set dfCell = dws.Range(dFirstCellAddress)
Dim drg As Range: Set drg = dfCell.Resize(srg.Rows.Count, srg.Columns.Count)
drg.Value = srg.Value
End Sub
Sub CopyValuesShorter()
Dim srg As Range
Set srg = ThisWorkbook.Worksheets("A").Range("A1").CurrentRegion
Dim drg As Range
Set drg = ThisWorkbook.Worksheets("B").Range("A1") _
.Resize(srg.Rows.Count, srg.Columns.Count)
drg.Value = srg.Value
End Sub
Sub CopyValuesShortest()
With ThisWorkbook.Worksheets("A").Range("A1").CurrentRegion
ThisWorkbook.Worksheets("B").Range("A1") _
.Resize(.Rows.Count, .Columns.Count).Value = .Value
End With
End Sub