How not to reload an excel Addin - excel

Question

I have built an Excel Macro (as an Excel Addin) to randomly generate numbers.
I built it because the rand() function on excel keep generating new numbers at each action in the Excel file. So I tried to build something that "freeze" the formula once it has generated a number.
It works pretty well but when I close the file and reopen it, the numbers change.
How can I fix that ?
I have tried something like : If current cell = Blank ==> generate, otherwise exit function. But it doesn't work.
Here is the code I'm using :
Function RandomFreeze()
Static AlreadyRandomized As Boolean
AlreadyRandomized = False
Static Low As Double
Static High As Double
Low = 1
High = 100000000
If Worksheets("Sheet1").Range("A1") = "" Then
If AlreadyRandomized = False Then
RandomFreeze = Int(Rnd * (High + 1 - Low)) + Low
AlreadyRandomized = True
End If
Else
MsgBox "Erreur"
AlreadyRandomized = True
End If
End Function
Any help with this issue will be appreciated.
Thanks in advance

Answer 1

You can store the value of AlreadyRandomized variable to a CustomDocumentProperty and read/set its value accordingly.
Public Sub T()
Dim p As Object
Set p = CustomPropertyByName("AlreadyRandomized")
If Not CBool(p.Value) Then 'Randomize
p.Value = True 'Randomized
End Sub
Two helper functions, one creates the property if it doesn't exist and returns a reference to it and the second simply checks if the property exists.
'CustomPropertyByName()
Public Function CustomPropertyByName(ByVal propertyName As String) As Object
If Not PropertyExists(propertyName) Then
ThisWorkbook.CustomDocumentProperties.Add Name:=propertyName, _
LinkToContent:=False, _
Type:=msoPropertyTypeNumber, _
Value:=0
End If
Set CustomPropertyByName = ThisWorkbook.CustomDocumentProperties(propertyName)
End Function
'PropertyExists()
Private Function PropertyExists(ByVal propertyName As String) As Boolean
Dim p As Object
For Each p In ThisWorkbook.CustomDocumentProperties
If p.Name = propertyName Then
PropertyExists = True
Exit Function
End If
Next p
End Function
Note: A runtime error occurs if you try to access a CustomDocumentProperty that doesn't exist.