Passing Arrays

[VSCurtis]

Hi Guys,



I am having a bit of a problem. I have a function which passes an array by reference. The Array is unallocated. The purpose of the function is to increase the array size by one as needed by the program. Arrays passed by reference should reflect any changes made by the function. This is not happening. The redim and redim preserve modifications made by the function are only visible inside the function. Once my code exits the function and returns to the main body of code the array shows that it is still unallocated and produces and error 9 subscript out of range. The only way I can get the function to preform as expected is to pass the array out of the function. Not sure what's going on here. Any help would be appreciated. Here's the code.

Private Function Test(aImageArray As Variant) As Variant
On Error Resume Next
   If IsArray(aImageArray) Then
      If IsError(LBound(aImageArray, 1)) Then
         Select Case Err.Number
            Case 9
              ReDim aImageArray(0)
          End Select
       Else
          ReDim Preserve aImageArray(UBound(aImageArray) + 1)
       End If
    End If
    Debug.Print UBound(aImageArray)
    Test = aImageArray
    
End Function

When coded like this the code functions as I want, but I should not have to pass the array out in order for the array to be resized. What's going on?

[ssanfu]

I rarely use arrays, but Chip Pearson has info about arrays:

Functions For VBA Arrays
http://www.cpearson.com/excel/VBAArrays.htm

Passing And Returning Arrays With Functions
http://www.cpearson.com/excel/Passin...ningArrays.htm


Or maybe https://msdn.microsoft.com/en-us/lib...v=vs.100).aspx



Maybe these will help........

[VSCurtis]

Yes I am aware of Chip's website. My function is based on one his. The function originally just checked to see if the array was allocated. Mine attempts to correct the issue. I leave the array unallocated so it can grow as needed according to the needs of the program. I will give the links you provided a look. Thanks

[davegri]

You might also check out vba collections. I find them easier to understand and manage than arrays.
http://alystcave.com/vba-collection/

[VSCurtis]

Thanks for your info but the page cannot be displayed

[davegri]

http://analystcave.com/vba-collection/

Well, spelling counts...

[VSCurtis]

Thanks for the info I'll check it out. I've used then before but it's been awhile.

[June7]

The only way I have made an array available to multiple procedures is to declare it as Global in general module. Then I don't have to 'pass' it. Any procedure can find the array. One procedure redims and sets the array elements. Another procedure uses the array elements.

[VSCurtis]

Of this I am already aware but thanks for the input