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Iterating user collections

Posted on 1998-11-25
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Last Modified: 2010-05-03
I have a class Chair in my system. Now I want to deal with typed collections of chairs, so I have defined a ColChair class, with a collection-like interface: Add, Remove, Item and Count. I have made Item the defaut property. The problem is I can't iterate the collection with a "For Each" construct; it crashes at run-time:

  Dim col As New ColChair
  'fill col with Chair objects.
  Dim ch As Chair
  For Each ch In col 'this line crashes.
    'do something with ch.
  Next ch

Any ideas?.

Regards,
César.
0
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Question by:CesarGon
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3 Comments
 
LVL 8

Expert Comment

by:MikeP090797
ID: 1446794
What error to you get?
0
 

Accepted Solution

by:
Belgarion_aus earned 100 total points
ID: 1446795
Add the following method to your collection class:

Public function NewEnum() as IUnknown
   
    Set NewEnum = mycollection.[_NewEnum]

End Function

Yes, the square brackets [] MUST be there !

Now go to tools/Procedure Attributes

In the name box select the NewEnum Method,

click advanced and select hide this member,

In Procedure Id box type -4. -4 is the procedure ID that implements For Each....Next.

And your done! Now For Each....Next will work.


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LVL 3

Author Comment

by:CesarGon
ID: 1446796
Thanks for your reply. It really works!. To satisfy my curiosity, please may you tell me where you learnt the solution?.

Regards,
César.

0

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