Using a generic class as a property

[Matthias S.]

Hi,

I have a class (say Company) which should expose a ReadOnlyCollection
property (say EmployeesCol) hosting userdefined types (Employee).

Since only the internals of the Company class should be allowed to
modify the EmployeesCol, I'd like to expose a read only collection as a
property, so that the users of my Company class can enumerate the
employes, but can't add or remove those.

I think this can be done using the ReadOnlyCollection<T> generic, but I
don't seem to understand the way of using this properly. Do I have to
derive from ReadOnlyCollection<T> or can I just use it in a property
declaration.

It would be nice if somebody could help me getting startet on this one.

Thanks in advance,

Matthias

[Nicholas Paldino [.NET/C# MVP]]

Matthias,

You can use the ReadOnlyCollection<T>. What I would do is keep a
List<T> (where T is Employee) internally in your Company class. When you
expose the ReadOnlyCollection, have it wrap the list you are holding
internally.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Matthias S." <po*****@emvoidSPAMTRAP.de> wrote in message
news:O1****************@TK2MSFTNGP09.phx.gbl...

Hi,

I have a class (say Company) which should expose a ReadOnlyCollection
property (say EmployeesCol) hosting userdefined types (Employee).

Since only the internals of the Company class should be allowed to modify
the EmployeesCol, I'd like to expose a read only collection as a property,
so that the users of my Company class can enumerate the employes, but
can't add or remove those.

I think this can be done using the ReadOnlyCollection<T> generic, but I
don't seem to understand the way of using this properly. Do I have to
derive from ReadOnlyCollection<T> or can I just use it in a property
declaration.

It would be nice if somebody could help me getting startet on this one.

Thanks in advance,

Matthias

[Matthias S.]

Thanks Nicholas!

Ok, spend some time reading just about anything that deals with
generics, and acutally, they are pretty cool :). Got it done in no time.

Thanks for the fast response!

Matthias

Nicholas Paldino [.NET/C# MVP] wrote:

Matthias,

You can use the ReadOnlyCollection<T>. What I would do is keep a
List<T> (where T is Employee) internally in your Company class. When you
expose the ReadOnlyCollection, have it wrap the list you are holding
internally.

Hope this helps.