Manually increment an enumerator inside foreach loop

Question

I have a nested while loop inside a foreach loop where I would like to advance the enumerator indefinitately while a certain condition is met. To do this I try casting the e

Answer 1

One alternative not yet mentioned is to have an enumerator return a wrapper object which allows access to itself in addition to the data element being enumerated. For sample:

struct ControllableEnumeratorItem
{
  private ControllableEnumerator parent;
  public T Value {get {return parent.Value;}}
  public bool MoveNext() {return parent.MoveNext();}
  public ControllableEnumeratorItem(ControllableEnumerator newParent)
    {parent = newParent;}
}

This approach could also be used by data structures that want to allow collections to be modified in controlled fashion during enumeration (e.g. by including "DeleteCurrentItem", "AddBeforeCurrentItem", and "AddAfterCurrentItem" methods).