internal void Replace(string idToUpdate, Rock rock)
{
if (rock == null)
{
throw new ArgumentNullException("rock");
}
int index = IndexOf(idToUpdate);
if (index == -1)
{
throw new ArgumentException("Supplied ID not found in collection.");
}
//Remove the rock from the collection.
Rocks.RemoveAt(index);
//Verify the (possibly changed) ID not in collection already
if (IndexOf(rock.UniqueId) != -1)
{
throw new ArgumentException("A rock with the specified ID already exists in the collection.");
}
//Insert the new rock at the same place.
Rocks.Insert(index, rock);
}
