Store tal der skal lææges sammen

Er der nogen der kan lave, ved hvor jeg kan hente noget kode der kan lægge meget store tal sammen uden at det bliver til 5e+632.
Eller også bare rette nedenstående så det virker.
Ingen point hvis det ikke virker.

på forhånd tak!

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Option Explicit

Public Function CalcAdd(Number1 As String, Number2 As String) As String
Dim i As Integer
Dim BlockSize As Integer
Dim BlockCount As Integer

BlockCount = 100
Dim NumberArray(3, 100) As Long
\'  +----------------- - - - - -
\' 0| Add
\'  +----------------- - - - - -
\' 1| Number1
\'  +----------------- - - - - -
\' 2| Number2
\'  +----------------- - - - - -
\' 3| Result
\'  +----------------- - - - - -
BlockSize = 1

\'Put number1 into place
For i = 0 To BlockCount
    NumberArray(1, i) = Right(Number1, BlockSize)
    Number1 = Mid(Number1, BlockSize + 1, Len(Number1) - BlockSize)
    If Len(Number1) = 0 Then Exit For
Next

\'Put number2 into place
For i = 0 To BlockCount
    NumberArray(2, i) = Right(Number2, BlockSize)
    Number2 = Mid(Number2, BlockSize + 1, Len(Number2) - BlockSize)
    If Len(Number2) = 0 Then Exit For
Next

\'Adds number1 and number2 together into result
Dim TempNumber As String
For i = 0 To BlockCount
    TempNumber = NumberArray(0, i) + NumberArray(1, i) + NumberArray(2, i)
    If Len(TempNumber) > BlockSize Then
        NumberArray(3, i) = Right(TempNumber, BlockSize)
        NumberArray(0, i + 1) = Left(TempNumber, Len(TempNumber) - BlockSize)
        \'MsgBox Left(TempNumber, Len(TempNumber) - BlockSize)
        \'Stop
    Else
        NumberArray(3, i) = TempNumber
    End If
    If TempNumber = 0 Then Exit For
Next

\'Takes all the resultblocks and puts then in one line before sending them back
Dim FinishNumber As String
FinishNumber = \"\"
For i = 0 To BlockCount
    If Not NumberArray(3, i) = 0 Then
        FinishNumber = NumberArray(3, i) & FinishNumber
        \'Stop
    End If
Next
CalcAdd = FinishNumber
End Function
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