Getting week number in PowerPoint - vba

Question

I have got a code to generate PowerPoint with an Excel file. I have mostly modified the code as per my requirement, but I want to add one more feature into my .ppt. I want VBA to extract Week Number from some source and do the following:
Rename my .ppt as "XXX_Weeknumber.ppt"
In one of the textboxes in the slides I want to add the same Weeknumber.
I tried getting the week number by using the function WeekNum and trying to call the function in my Main Sub but unfortunately doesn't work!
My code for function in Module 1:
Function WeekNum(D As Date) As Integer
WeekNum = CInt(Format(D, "ww", 2))
End Function
Code for the .xls to .ppt in Module 2:
Dim oPPTApp As PowerPoint.Application
Dim oPPTShape As PowerPoint.Shape
Dim oPPTShape2 As PowerPoint.Shape
Dim oPPTFile As PowerPoint.Presentation
Dim PPSlide As PowerPoint.slide
Dim SlideNum As Integer
Dim rng As Range
Dim WeekNumm$
Sub PPTableMacro()
Dim sourcexl As Workbook
Dim wk As Integer
Dim strPresPath As String, strExcelFilePath As String, strNewPresPath As String
strExcelFilePath = "C:\MySource.xls"
strPresPath = "C:\Presentation1.ppt"
Call WeekNum
WeekNumm = WeekNum()
Set wk = WeekNumm
strNewPresPath = "C:\Presentation1_" & wk & ".ppt" 'This is how I want the name
strNewPresPath = "C:\new1.ppt"
Set oPPTApp = CreateObject("PowerPoint.Application")
oPPTApp.Visible = msoTrue
Set oPPTFile = oPPTApp.Presentations.Open(strPresPath)
SlideNum = 2
oPPTFile.Slides(SlideNum).Select
Set oPPTShape = oPPTFile.Slides(SlideNum).Shapes("Table 1")
Set sourcexl = Workbooks.Open(strExcelFilePath) 'Source excel file
With sourcexl
.Sheets("Sheet1").Activate
oPPTShape.Table.Cell(1, 1).Shape.TextFrame.TextRange.Text = Cells(1, 1).Text
oPPTShape.Table.Cell(1, 2).Shape.TextFrame.TextRange.Text = Cells(1, 2).Text
oPPTShape.Table.Cell(1, 3).Shape.TextFrame.TextRange.Text = Cells(1, 3).Text
oPPTShape.Table.Cell(2, 1).Shape.TextFrame.TextRange.Text = Cells(2, 1).Text
oPPTShape.Table.Cell(2, 2).Shape.TextFrame.TextRange.Text = Cells(2, 2).Text
oPPTShape.Table.Cell(2, 3).Shape.TextFrame.TextRange.Text = Cells(2, 3).Text
End With
Set oPPTShape2 = oPPTFile.Slides(SlideNum).Shapes("TextBox 1")
Text1 = "weekXX" ' actually wanted week number here
oPPTShape2.TextFrame.TextRange.Text = Text1
oPPTFile.SaveAs strNewPresPath
'oPPTFile.Close
'oPPTApp.Quit
Set oPPTShape = Nothing
Set oPPTFile = Nothing
Set oPPTApp = Nothing
MsgBox "Presentation Created", vbOKOnly + vbInformation
End Sub

Answer 1

Your function asks for a data input ("D"), and it's not optional. If you want to retrieve the day of the week of today ("Date" system variable), you should call it like this:
WeekNumm = WeekNum(Date)
Also, you are using a Set statement in "Set wk = WeekNumm". As the variable isn't an object, you have to use (a preferably omitted) Let.
Also, your function will not return the day of the week, because "ww" means the week number of the year. If you want the day of the week by this approach, you have to use "w".
For a better approach, you should use the builtin function Weekday to get the weekday.
Like:
iWeekDay = Weekday(Date,vbUseSystemDayOfWeek) 'Retrieves today's day of the week (Tuesday = 3...)