Interface and collections

[Lee]

Assuming I have an interface defined:

public interface IDTPersistableCollection: IList<IDTPersistableObject>
{
//Few specific properties defined

}

When I try to create an object based on this, I get all kind of errors
about members not being implemented such as this one:

Error 3 'AbstrationTestApp.Classes.CollectionBasic' does not implement
interface member
'System.Collections.Generic.IList<DTAbstraction.Interfaces.IDTPersistabl
eObject>.RemoveAt(int)'

I understand that I have to implement the required members of the
interface I'm implmementing. But, because I am using an interface, I
don't understand what it's asking for. I try to implement the RemoveAt
method, but still get errors.

Is there another trick to implementing collections using interfaces
that I am missing?

If figure 4 hours of trying to figure it out without success warrants a
post for help, LOL.

Thanks for any help,

--
Warm Regards,
Lee

"Upon further investigation it appears that your software is missing
just one thing. It definitely needs more cow bell..."

 

[Marc Gravell]

If you are using the IDE, the trick is to get VS to stub it out for you; in
2003 you can do this involving [Tab] and some luck; in 2005 you right-click
on the interface and choose "implement" (choosing explicit etc as you like).

I ran your code through this, and it gives me the following; plenty to fill
in ;-p

Marc

public interface IDTPersistableObject { }
public interface IDTPersistableCollection : IList<IDTPersistableObject>
{
void SomeOtherMethod(int param);

}
public class MyClass : IDTPersistableCollection {

public void SomeOtherMethod(int param) {
throw new Exception("The method or operation is not
implemented.");
}
public int IndexOf(IDTPersistableObject item) {
throw new Exception("The method or operation is not
implemented.");
}
public void Insert(int index, IDTPersistableObject item) {
throw new Exception("The method or operation is not
implemented.");
}
public void RemoveAt(int index) {
throw new Exception("The method or operation is not
implemented.");
}
public IDTPersistableObject this[int index] {
get {
throw new Exception("The method or operation is not
implemented.");
}
set {
throw new Exception("The method or operation is not
implemented.");
}
}
public void Add(IDTPersistableObject item) {
throw new Exception("The method or operation is not
implemented.");
}
public void Clear() {
throw new Exception("The method or operation is not
implemented.");
}
public bool Contains(IDTPersistableObject item) {
throw new Exception("The method or operation is not
implemented.");
}
public void CopyTo(IDTPersistableObject[] array, int arrayIndex) {
throw new Exception("The method or operation is not
implemented.");
}
public int Count {
get { throw new Exception("The method or operation is not
implemented."); }
}
public bool IsReadOnly {
get { throw new Exception("The method or operation is not
implemented."); }
}
public bool Remove(IDTPersistableObject item) {
throw new Exception("The method or operation is not
implemented.");
}
public IEnumerator<IDTPersistableObject> GetEnumerator() {
throw new Exception("The method or operation is not
implemented.");
}
System.Collections.IEnumerator
System.Collections.IEnumerable.GetEnumerator() {
throw new Exception("The method or operation is not
implemented.");
}
}

 

[Lee]

Marc Gravell enlightened me by writing:

If you are using the IDE, the trick is to get VS to stub it out for
you; in 2003 you can do this involving [Tab] and some luck; in 2005
you right-click on the interface and choose "implement" (choosing
explicit etc as you like).

I ran your code through this, and it gives me the following; plenty
to fill in ;-p

Marc

Thanks for the info. I was confused because I thought I only had to
implment the Ilist specific members, but as it turns out, logically I
have to include ICollection members as well.

Thanks again,

--
Warm Regards,
Lee

"Upon further investigation it appears that your software is missing
just one thing. It definitely needs more cow bell..."