How to merge several arrays of Outlook items into one big array

I do collections of Outlook items with VBA taking items from particular Outlook folders.

In the Excel VBA code below I collect items from two folders into two arrays.

Set olGetArchMeetings = olNS.Folders(2).Folders(4).Items
olGetArchMeetings.IncludeRecurrences = True
olGetArchMeetings.Sort "[Start]"
strRestrictionArch = "[Start] >= '" & mStart & "' AND [End] <= '" & mEnd & "'"
Set objArray1 = olGetArchMeetings.restrict(strRestrictionArch)
    
Set olGetMeetings = olNS.GetDefaultFolder(9).Items 
olGetMeetings.IncludeRecurrences = True
olGetMeetings.Sort "[Start]"
strRestriction = "[Start] >= '" & mStart & "' AND [End] <= '" & mEnd & "'"
Set objArray2 = olGetMeetings.restrict(strRestriction)

Is there any way to merge two arrays of objects into one?

I want to add all items from objArray2 to the end of objArray1 and make a new array that will contain items from both arrays?

I tried to merge via basic array joining like merging string arrays.

First of all, the Restrict method of the Items class applies a filter to the Items collection, returning a new collection containing all of the items from the original that match the filter, but not an array.

> The questions is: Is there any way to merge two arrays of objects into one? Like add all items from objArray2 to the end of objArray1 and therefore make a new Array that will contain itmes from both arrays?

No, there is no trivial way of getting a single Items collection from different Restrict calls. You may consider building an array of data extracted from items found. But a better yeat approach is to use a single search which can be run in the background in Outlook.

The Application.AdvancedSearch method allows performing a search based on a specified DAV Searching and Locating (DASL) search string in multiple folders. To specify multiple folder paths, enclose each folder path in single quotes and separate the single quoted folder paths with a comma.

The key benefits of using the AdvancedSearch method in Outlook are:

• The search is performed in another thread. You don’t need to run another thread manually since the AdvancedSearch method runs it automatically in the background.
• Possibility to search for any item types: mail, appointment, calendar, notes etc. in any location, i.e. beyond the scope of a certain folder. The Restrict and Find/FindNext methods can be applied to a particular Items collection (see the Items property of the Folder class in Outlook).
• Full support for DASL queries (custom properties can be used for searching too). To improve the search performance, Instant Search keywords can be used if Instant Search is enabled for the store (see the IsInstantSearchEnabled property of the Store class).
• You can stop the search process at any moment using the Stop method of the Search class.

Read more about that in the article that I wrote for the technical blog: Advanced search in Outlook programmatically: C#, VB.NET.

I have no clue on how to code for outlook, but basic array merging would be like this. That is code for one-dimensional arrays only:

Sub ArrayMerge()

Dim obA As Object, obB As Object, obC As Object, obD As Object
Dim arrA As Variant, arrB As Variant, arrAll As Variant
Dim m As Integer, n As Integer, first As Integer, last As Integer

'setting objects
Set obA = Cells(1)
Set obB = Cells(2)
Set obC = Cells(3)
Set obD = Cells(4)

'dimensioning arrays
ReDim arrA(1 To 2)
ReDim arrB(1 To 2)

'filling both arrays
Set arrA(1) = obA
Set arrA(2) = obB

Set arrB(1) = obC
Set arrB(2) = obD

first = UBound(arrA) + 1             ' = 3 
last = UBound(arrA) + UBound(arrB)   ' = 4

'Enlarge the first array to join the second one
ReDim Preserve arrA(1 To last)
 
   For m = first To last
       n = n + 1
       Set arrA(m) = arrB(n)
   Next m

End Sub