vbaCastObj

Returns an object reinterpreted as another COM interface, given its IID, or Nothing if the object does not implement that interface.

Syntax: vbaCastObj( Obj , IID ) As IUnknown

Obj
required stdole.IUnknown. The object to cast.
IID
required Any. The interface ID to query for — accepted as a 16-byte GUID structure or as a String in registry format ({xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}).

A direct wrapper over IUnknown::QueryInterface: the object is asked whether it implements the requested interface, and if so a reference to that interface is returned. If not, Nothing is returned.

Example 

Const IID_IPicture As String = "{7BF80980-BF32-101A-8BBB-00AA00300CAB}"

Dim Pic As Object = LoadPicture("logo.bmp")
Dim AsPicture As IUnknown = vbaCastObj(Pic, IID_IPicture)
If Not AsPicture Is Nothing Then
    ' Use AsPicture as an IPicture.
End If

See Also