Foreach

Tuesday, May 04, 2004 11:48 PM

Nick Hodges, my TeamB colleague and a confessed Delphi-zealot, just found out that the C# compiler actually converts foreach constructs on arrays to for statements. Microsoft's Brad Adams covered this in a recent post. If you're keeping score, Nick, you'd love this: sometimes, foreach is slower than for.

The performance difference, however, is negligible. The important point is that foreach isn't "syntactical sugar" - it has a definite purpose in life. If all you want to do is iterate through an entire array, then foreach is syntactically identical to for (and therefore generates the same IL). Other cases are not so simple. Foreach and for loops are not identical, as Raymond Chen demonstrates. And, in my opinion, foreach is far more convenient when used on types other than arrays, providing direct access to IEnumerable interfaces.

By the way: I'm moving this blog to a new host, so this page may down be until the DNS changes kick in. If you can't read this, that's the reason.