Question

I am thinking about a re-factor, but I don’t know if the end result is just overkill.
Currently I have

    IList<myobjecttypebase> m_items;

   public int GetIncrementTotal()
   {
     int incrementTot;
     foreach(myobjecttypebase x in m_items)
     { incrementTot += x.GetIncrement(); }
   }

Would it be overkill and/or less efficient to use linq for the ForEach

m_items.ToList().ForEach(x => incrementTot += x.GetIncrement());

Would the cast be a significant overhead here?

Answer 1

The ToList method is an extension method used with LINQ, but the ForEach method is just a method in the List class.

The major overhead here is the call to the ToList method, which creates a new List from the collection. The ForEach also has a slight overhead as it has to call a delegate for each item.

If you want to use LINQ methods, the Aggregate method seems more appropriate:

public int GetIncrementTotal() {
  return m_items.Aggregate(0, (t, i) => t + i.GetIncrement());
}

Or Sum:

public int GetIncrementTotal() {
  return m_items.Sum(i => i.GetIncrement());
}

Either has a slight overhead over your original version, so if you want the most efficient, just stick to a simple loop.