Why is this List<>.IndexOf code so much faster than the List[i] and manual compare?

Question

I\'m running AQTime on this piece of code, I found that .IndexOf takes 16% of the time vs close to 80% for the other piece... They appear to use the same IsEqual and other rout

Answer 1

What's the type of _pCoord3Points? If the element type is a value type which only overrides Equals(object) then it's possible that IndexOf is repeatedly boxing values to check for equality. That might explain it. It's really just guesswork at this point though... if you could provide a short but complete program which demonstrates the problem, that would make it a lot easier to help you.