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Custom control: Allow null property value

I have created a custom control, and for one of its properties it is
possible that the value may be null. However, at design time when a null
value is assigned, I get the error "The object 'myControl1' returned null
for the property 'TheProperty' but this is not allowed".

The property itself is a custom Collection object (extending
CollectionBase), so I could use an empty collection instead of null as a
last resort, but I would much rather have a null object instead.

How can I allow null values?

Thanks,

Derrick
Nov 16 '05 #1
1 2809
Using an empty collection is the preferred way to design libraries.
-mike
MVP

"Derrick" <de***********@hotmail.com> wrote in message
news:sy*********************@news20.bellglobal.com ...
I have created a custom control, and for one of its properties it is
possible that the value may be null. However, at design time when a null
value is assigned, I get the error "The object 'myControl1' returned null
for the property 'TheProperty' but this is not allowed".

The property itself is a custom Collection object (extending
CollectionBase), so I could use an empty collection instead of null as a
last resort, but I would much rather have a null object instead.

How can I allow null values?

Thanks,

Derrick


Nov 16 '05 #2

This thread has been closed and replies have been disabled. Please start a new discussion.

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