In .NET, which loop runs faster, 'for' or 'foreach'?

Question

In C#/VB.NET/.NET, which loop runs faster, for or foreach?

Ever since I read that a for loop works faster than a foreach

Answer 1

Jeffrey Richter on TechEd 2005:

"I have come to learn over the years the C# compiler is basically a liar to me." .. "It lies about many things." .. "Like when you do a foreach loop..." .. "...that is one little line of code that you write, but what the C# compiler spits out in order to do that it's phenomenal. It puts out a try/finally block in there, inside the finally block it casts your variable to an IDisposable interface, and if the cast suceeds it calls the Dispose method on it, inside the loop it calls the Current property and the MoveNext method repeatedly inside the loop, objects are being created underneath the covers. A lot of people use foreach because it's very easy coding, very easy to do.." .. "foreach is not very good in terms of performance, if you iterated over a collection instead by using square bracket notation, just doing index, that's just much faster, and it doesn't create any objects on the heap..."

On-Demand Webcast: http://msevents.microsoft.com/CUI/WebCastEventDetails.aspx?EventID=1032292286&EventCategory=3&culture=en-US&CountryCode=US