How to access an array directly that is returned from a function in VBScript

Question

I have a function of a COM object that returns an Array.

This code works

Dim a a = obj.Foo MsgBox a(0)

This code says that there is no enumeration. And it is true.

MsgBox obj.Foo(0)

Also this didn't worked

MsgBox (obj.Foo)(0)

The problem is that the Foo function is a simple property.

Is there a syntax to directly access the data member?

Edit: Just to make clear that the function works correctly IsArray(obj.Foo) returns true!

You should be able to do something like obj.Foo(0).get() or obj.Foo(0).FirstOrDefault(). I am not entirely sure about how you get the result since I am not an expert in vb but I believe there should be something that can be called as I suggest. — Ali Beyit
– Ali Beyit, Commented Dec 18, 2019 at 10:36
It depends what data type the COM object returns, VBScript expects a VT_ARRAY so you'll need to marshal the return type visible to COM. — user692942
– user692942, Commented Dec 18, 2019 at 11:03
Does this answer your question? How to correctly marshal VB-Script arrays to and from a COM component written in C# — user692942
– user692942, Commented Dec 18, 2019 at 11:45
The Array is a SAFEARRAY of VARIANTs. Otherwise the first method wouldn't work. — xMRi
– xMRi, Commented Dec 18, 2019 at 12:06

Roman Ryltsov · Accepted Answer · 2019-12-20 09:24:23Z

I believe the problem here is that variant array returned via COM needs to become a VB collection object, which does not happen immediately.

It happens when there is an intermediate variable, but it does not yet happen in the case of expression. In the latter case VBScript already sees what it treats as an object, but this object is a thin wrapper over variant array and it is not yet a collection object.

If you want a VBS one liner, this would work out:

Function TrueArray(ByVal Value) TrueArray = Value End Function 'MsgBox obj.Foo(0) -- Object not a collection: 'obj.Foo' MsgBox TrueArray(obj.Foo)(0)

You can also implement a collection on the other side of property implementation and return it instead of safe array (ATL C++ code would use CComEnum<IEnumVARIANT... helper, example).

I realize that your question is more about built-in scripting language capability that does the required conversion. Perhaps you could use some of the built-in functions to perform a similar trick to TrueArray above.

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