DotNetKicks.com - Stories tagged with foreach

Lists: Filter, Map and Reduce - and the Magic of IEnumerator.

Tue, 26 Aug 2008 01:49:30 GMT

There are 3 very handy list functions which make dealing with lists a breeze: Map, Filter and Reduce. But along the way of writing them, an important principle of IEnumerator<> comes up.

Why System.Linq.Enumerable doesn't have a ForEach extension method

Mon, 30 Jun 2008 15:14:43 GMT

Lots of people suggest a ForEach method would be a good addition to the base class framework. This is why I don't think it would be, even though our core library has an implementation of it.

JavaScript ForEach Equivalent

Fri, 29 Feb 2008 00:29:28 GMT

One thing with the For Loop in JavaScript is it doesn't seem to be very well documented that you can use it to do an equivalent of a ForEach loop. Here's a short example of doing the ForEach loop equivalent in JavaScript using the "in" keyword.

Create elegant code with Action delegate and List.ForEach method

Mon, 12 Nov 2007 12:46:02 GMT

Small example of how to use Action delegate to perform some action on all elements of a collection.

What's inside a foreach() statement?

Fri, 18 May 2007 07:46:49 GMT

A comparision of a foreach() loop and manually looping by calling GetEnumerator() and MoveNext()

Only iterating over the objects you want in a foreach loop

Sun, 25 Feb 2007 12:01:01 GMT

Have you ever had a collection made of several types which all derive from the same base class? How many times have you needed to iterate the whole collection and check each element to make sure its the type that you want to work with? Here's how to do you type checking completely inline inside of the foreach loop so you only get the objects you want.

Performance of foreach vs. List.ForEach

Sat, 07 Oct 2006 08:01:02 GMT

Today I was iterating a List<int> using a foreach-loop and feeling a bit smug in knowing how much more performance-conscious I was being than if I'd tried doing the same thing with an ArrayList filled with ints. Thanks to the wonder of generics, the C# compiler neatly avoids numerous boxing operations by using a System.Collections.Generic.IEnumerator<int> instance instead of the older System.Collections.IEnumerator. Then I got to thinking: "is this really the fastest way?" Upon investigation, it turns that, no, it isn't the fastest way.