IEnumerable vs IEnumerable<T>

[nick_tucker@hotmail.com]

Hi,

Could someone tell me which of the following is correct if I want to
make the MyCollection class below enumerable

public class MyCollection:Sy stem.Collection s.IEnumerable
{
private List<MyItem> m_MyItemsList

System.Collecti ons.IEnumerator
System.Collecti ons.IEnumerable .GetEnumerator( )
{
return m_MyItemsList.G etEnumerator();
}
}

is this fine or should I use the generic IEnumerable interface i.e.


public class MyCollection:IE numerable<MyIte m>
{
private List<MyItem> m_MyItemsList

System.Collecti ons.IEnumerator
System.Collecti ons.IEnumerable .GetEnumerator( )
{
return m_MyItemsList.G etEnumerator();
}

public IEnumerator<MyI tem> GetEnumerator()
{
foreach (MyItem oItem in m_MyItemsList)
yield return oItem;
}
}

Are the two classes do the same thing when I the use foreach on
MyCollection class??

Thanks,
Nick

[Marc Gravell]

Re: IEnumerable vs IEnumerable&lt; T&gt;

Well, using the generic enumerator can prevent runtime errors of the type
"foreach(WrongC lass x in something)", as they are caught at compile-time
instead; so I would stick with IEnumerable<MyI tem>.

As for the second block of code - any reason why you have used the yield
return construct? since this is just enumerating the list, and List<T> :
IEnumerable<T>, then "return m_MyItemsList.G etEnumerator(); " should be
sufficient? does this fail?

Marc