The Delete method removes the Pattern object from the Patterns collection.
objPattern.Delete( )
The Delete method performs an irreversible operation on the collection. It calls Release on the collection's reference to the Pattern object. If you have another reference to the pattern, you can still access its properties and methods, but you can never again associate it with any collection because the Add method always creates a new object. You should Set your reference variable either to Nothing or to another pattern.
The final Release on the Pattern object takes place when you assign your reference variable to Nothing, or when you call Delete if you had no other reference. At this point the object is removed from memory. Attempted access to a released object results in an error return of CdoE_INVALID_OBJECT.
The action of the Delete method is permanent, and the Pattern object cannot be restored to the collection. Before calling Delete, your application can prompt the user to verify whether the pattern should be permanently deleted.
When you delete a member of a collection, the collection is immediately refreshed, meaning that its Count property is reduced by one and its members are reindexed. To access a member following the deleted member, you must use its new index value. For more information, see Looping Through a Collection.
This code fragment illustrates the two situations previously explained. The Set statement calls AddRef on the first Pattern object. That reference survives the call to Delete and has to be reassigned. The second Pattern object is deleted without creating another reference, and no other action is necessary.
' assume valid Format object
Set objPattern = objFormat.Patterns.Item(1)
objPattern.Delete ' still have a reference from Set statement
' ... other operations on objPattern possible but pointless ...
Set objPattern = Nothing ' necessary to remove reference
' ...
objFormat.Patterns.Item(2).Delete ' no reference to remove