Types of Interface in C#

Interfaces define properties, methods, and events, which are the members of the interface.Interfaces contain only the declaration of the members.

Some of the interface types in C# include.

• IEnumerable − Base interface for all generic collections.
• IList − A generic interface implemented by the arrays and the list type.
• IDictionary − A dictionary collection.

IEnumerable is an interface defining a single method GetEnumerator that returns an IEnumerator interface.

This works for readonly access to a collection that implements that IEnumerable can be used with a foreach statement.

The following shows the implementation of IEnumerable interface.

class Demo : IEnumerable, IEnumerator {
   // IEnumerable method GetEnumerator()
   IEnumerator IEnumerable.GetEnumerator() {
      throw new NotImplementedException();
   }
   public object Current {
      get { throw new NotImplementedException(); }
   }
   // IEnumertor method
   public bool MoveNext() {
      throw new NotImplementedException();
   }     
   // IEnumertor method
   public void Reset() {
      throw new NotImplementedException();
   }
}

Above you can see the two methods of IEnumerator.

// IEnumerator method
public bool MoveNext() {
   throw new NotImplementedException();
}     
// IEnumertor method
public void Reset() {
   throw new NotImplementedException();
}