Modify User Defined Data in A Function

[mturbett]

The code below works to the point MsgBox v.
Using watch I can see the data in the TD() and then data() in the function. Msgbox displays but contains nothing.
My goal is to fill or modify TD by passing to a function. Again using watch I can see the data in each variable. However I donot see the modified data in Main
Thank You
Marlin

REM  *****  BASIC  *****
'Test passing Used defined Data types to functions
Public Type TestData
	D1 as Long
	D2 as String
End Type

Sub Main

Dim TD(5) As New TestData
Dim i, j As Integer
Dim s as String
Dim v as Variant
j = 4



For i = 0 to j
		TD(i).D1 = i
		TD(i).D2 = Chr(134 + j * 2) & " More Data " & j^3
		s = s + "TD(" & i & ")= " & TD(i).D1  & Chr(13) & _
			"TD(" & i & ")= " & TD(i).D2  & Chr(13)
Next i
MsgBox s
	
v = SetTestData(TD())

MsgBox v
End Sub

Function SetTestData( data as Variant) as Variant
	Dim i As Integer
	For i = LBound(data) to UBound(data)
		data(i).D1 = i^2
		data(i).D2 = Chr(217 + j) & " Addtional Data " & j^3

	Next i
SetTestData = data()
End Function

[erAck: edited to format code as code … see This is the guide - How to use the Ask site? - #6 by erAck ]

[joshua4]

@Lupp is correct about User Defined Types. Perhaps here if you know that the size of TD is fixed then just Dim out TD as

Dim TD(0 To 5, 0 To 1) As Variant

and use the second dimension for your D1 and D2. For example, TD(4, 1) instead of TD(4).D2.

If you may have to ReDim your TD, then switch dimensions

Dim TD(0 To 1, 0 To 5) As Variant

Other hints:

1. Make sure you do use Option Explicit
2. Once you use arrays, show the world your intended lower bound with Option Base 0.

For example, I do not see where j is coming from in your SetTestData. You don’t pass it, and without Option Explicit you have no way to realize that it’s just a 0.

[Lupp]

For the output of the original data you prepare the string s by concatenation (as needed).
Why do you expect that MsgBox can output the array v of data of user defined type?
It can’t. But you can inspect the returned array.in the Watch pane.

In addition: Be careful when relying on user defined types. They often don’t behave as expected and needed. They probably are rarely used. A very old bug may have survived therefore for decades.
See https://bugs.documentfoundation.org/show_bug.cgi?id=146082