I am now using collections in c#. So , i want to please anyone can give me a brief intro with implementation of IEnumerable<> interface.
Thank You.
What is IEnumerable<> in C#?
237627-Jan-2016
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Anupam Mishra
28-Jan-2016In C# collection defines a non-generic IEnumerable interface and there is a generic type-safe IEnumerable<T> interface.
The IEnumerable interface is located in the System.Collections namespace and contains only a single method definition. The interface definition looks like this:
The GetEnumerator method must return an instance of an object of a class which implements the IEnumerator interface. I am not going to details. if you are interested, please visit the msdn documentation.
It is important to know that the C# language foreach keyword works with all types that implement the IEnumerable interface. Only in C# it also works with things that don’t explicitly implement IEnumerable or IEnumerable<T>. I believe you have been using the foreach keyword many times and without worrying about the reason why and how it worked with that type.
IEnumerable<T>
Let’s now take a look at the definition of the generic and type-safe version called IEnumerable<T> which is located in the System.Collections.Generic namespace:
?
public interface IEnumerable<out T> : IEnumerable
{
IEnumerator<T> GetEnumerator();
}
As you can see the IEnumerable<T> interface inherits from the IEnumerable interface. Therefore a type which implements IEnumerable<T> has also to implement the members of IEnumerable.
IEnumerable<T> defines a single method GetEnumerator which returns an instance of an object that implements the IEnumerator<T> interface. We won’t have a look at this interface this time. Please take a look at the msdn documentation if you would like to get some more information.