About interface ICollection

[Tony]

Hello!

I'm reading in book and it says the following.
"ICollection provides the ability to obtain the number of items in a
collection and to copy items into
a simple array type(inherits from IEnumerable)."

I have looked in interface ICollection and IEnumerable and there is no
method or property that
match in any way the last part of the statement from the book that says
"copy items into
a simple array type"

//Tony

 

[Marc Gravell]

Well, I'm not sure why it mentions "inherits from IEnumerable", since
that doesn't add anything here - but the answer is CopyTo:

ICollection data = new int[] { 1, 2, 3, 4, 5 };
int[] copy = new int[data.Count];
data.CopyTo(copy, 0);

Of course, in .NET 2.0 and above it would be preferable to use the
genric (typed) interfaces:

ICollection<int> data ...

This makes it more explicit that it expects CopyTo to operate on an
int[], rather than just an Array - and a lot of other things.

Marc

 

[Ignacio Machin ( .NET/ C# MVP )]

Hello!

I'm reading in book and it says the following.
"ICollection provides the ability to obtain the number of items in a
collection and to copy items into
a simple array type(inherits from IEnumerable)."

ICollection.Count does the counting part
ICollection.CopyTo does the copy part

I do not what CopyTo has to do with IEnumerable though.