When IEnumerator.Reset() method is called?

Question

let\'s have this code :

class MyList : IEnumerable, IEnumerator
{
    int[] A = { 1, 2, 3, 4, 5 };
    int i = -1;

    #region IEnumerator Members

    pub         


        

Answer 1

Reset is not called by foreach. Looking at your Main method in Reflector confirms this.

The .NET classes, like ArrayList, actually return a new instance of a class that implements IEnumerator.

For example ArrayList implements IEnumerable, and its GetEnumerator method looks like this:

public virtual IEnumerator GetEnumerator()
{
    return new ArrayListEnumeratorSimple(this);
}

so there is no need to worry about calling Reset since every foreach uses a new instance of the enumerator.

For a complete example showing the implementation of IEnumerable and a separate class implementing IEnumerator, you can look at the documentation for IEnumerable.