Determine the class of an object

[Edward Ulle]

I construct several classes and store them sequentually in a collection
as they are created. Each class is unique. To access a method of the
class I need to cast back to the original class type.

How can I determine the class type during runtime? See the following
pseudo code.

Dim myCollection as New Collection
Dim myClass1 as Class1
Dim myClass2 as Class2

Set myClass1 = new Class1
myCollection.Add Item:=myClass1
Set myClass2 = new Class2
myCollection.Add Item:=myClass2
set myClass1 = new Class1
myCollection.Add Item:=myClass1

Later

Dim nowClass1 as Class1
Dim nowClass2 as Class2

Set nowClass1 = myCollection.Item(1) ' Same class
Set nowClass2 = myCollection.Item(1) ' Not the same class

 

[keepITcool]

Edward Ulle wrote :

I construct several classes and store them sequentually in a
collection as they are created. Each class is unique. To access a
method of the class I need to cast back to the original class type.

How can I determine the class type during runtime? See the following
pseudo code.

Edward do you mean this?

Select case TypeName(myCollection(1))
case "Class1"
Set nowClass1 = myCollection(1)
case "Class2"
Set nowClass2 = myCollection(1)
End Select

 

[Edward Ulle]

Yes thank you.

I did not look at TypeName because I thought it only applied to user
defined types not classes.

Thanks again.

 

[Jamie Collins]

Edward Ulle wrote ...

I construct several classes and store them sequentually in a collection
as they are created.

Multiple class types in the same collection? This is a stab in the
dark but you may be interested in VBA's version polymorphism. See:

http://msdn.microsoft.com/library/d.../html/vbconinheritancepolymorphismallthat.asp

Jamie.

--

 

[Jamie Collins]

Edward Ulle wrote ...

Set myClass1 = new Class1
myCollection.Add Item:=myClass1
Set myClass2 = new Class2
myCollection.Add Item:=myClass2

Another thought: a Collection object has no functionality to retrieve
the key that was used to add an item. You may prefer to use an
'container' object that does e.g. a Dictionary object (I use a
fabricated ADO recordset myself, of course <g>).

Jamie.

--

 

[keepITcool]

Jamie Collins wrote :

... I use a fabricated ADO recordset myself, of course <g>).

Jamie.

--

shaped where possible

 

[Jamie Collins]

...

shaped where possible

Actually, my object models are hierarchical, not my collection classes <g>.

Jamie.

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