Krzysztof Cwalina

Peter Golde recently posted about the IsReadOnly and IsFixedSize change we made to the generic collection interfaces.There are also several other discussions around the net on this topic. I thought I write up something to explain the motivation and our...

I have received several comments asking what usability studies are and how to conduct them. Steven’s blog is one of the best sources of information on API usability studies. In particular the recent post on HOWTO: Run an API usability study .

The Design Guidelines have been published on MSDN and as a part of the CLI ECMA specification ( Partition V , Annex D). This was long time ago and we have been receiving lots of requests for an update and also for something that can be read offline. ...

Joe, just posted an update to the Design Guidelines describing issues relared to IDisposable, Finalization, and resource management....

Exception Throwing Exception throwing guidelines described in this section require a good definition of the meaning of execution failure. Execution failure occurs whenever a member cannot do what it was designed to do (what the member name implies). For...

Several people asked me why Collection<T>, ReadOnlyCollection<T>, and KeyedCollection<TKey,TValue> were moved to System.Collections.ObjectModel namespace. Here are the two main reasons: 1. Microsoft.VisualBasic namespace contains a non...

Lot ’s of people asked me why IEnumerator<T> extends IDisposable. We did this to support some obscure, yet important scenarios where an enumerator enumerates database rows, or files in a directory, etc. In such cases, the enumerator usually opens...

I just discovered a cool way of listing all processes that run managed code. using System.Diagnostics; using System; class Program { static void Test() { PerformanceCounterCategory clr = new PerformanceCounterCategory ( ".NET CLR Memory" ); foreach (...

The recent type parameter naming guidelines update resulted in a very lively discussion. I thought I would provide some rational for the recent changes. But first, I would like to first thank all of you who got involved in the debate. We have had debates...

I just noticed that the Power Collections project made it to the “Featured Sites” on GotDotNet. See http://www.gotdotnet.com/content/featuredsite/powercollections/default.aspx For those who don’t know, Power Collections is a community open source library...

After receiving lots of feedback from internal and external community (see here for example), we decided to modify the generic type parameter naming guidelines. The previous guidelines allowed only single letter type parameter names. The new guidelines...

We are exploring the possiblility of changing the design of IComparer<T> and IComparable<T> interfaces that will ship with Whidbey. This post describes some more detail on the issues we are trying to address with the design change and we are...

I often hear people saying that interfaces specify contracts. I believe this is a dangerous myth. Interfaces, by themselves, do not specify much beyond the syntax required to use an object. The interface-as-contract myth causes people to do the wrong...

Joe has recently spent some time beefing up the Factory vs. Constructor guidelines. This subject has been the center of lots of intenral debates. Finally, we agreed on the fllowing: Factories The most common and consistent way to create an instance of...

Lots of people have asked me to create a short version of the Design Guidelines. Here it is. You can also email me directly at kcwalina@microsoft.com if you would like to get an MS Word copy of the digest, hich has a bit better formatting. [UPDATE...

Kit George (member of the BCL team) blogged an update that we just did to our Design Guidelines. The new guidelines talk issues related to evolving managed APIs. See http://weblogs.asp.net/bclteam/archive/2004/09/07/226489.aspx

Somebody asked me a question how to set the initial capacity of System.Collections.Generic.Dictionary<K,V> if one knows that the Dictionary will contain 1000 entries. The short answer Dictionary<int,string> numbers = new Dictionary<int...

Generics and Anonymous Methods/Delegates make up a powerful pair that can be used to create elegant query APIs. Here are some that we just added to the .NET Framework’s Collection libraries. I used List<T> to illustrate the APIs but most of...

This is a relatively major update to the Design Guidelines. It describes and formalizes a very common .NET Framework Pattern/Idiom for exposing optional functionality/service of an API (for example canceling a stream operation, as not all streams support...

This is a recent update to the Design Guidelines. One of the most interesting additions is the section about adding values to enums (at the end of the section). This was one of the guidelines were getting an agreement across the whole company was quite...

Small update to the Design Guidelines courtesy of the XML team. System.Xml Usage Exposing XML Data Do provide overloads that accept and System.Xml.XmlReader and System.String for properties of a class that represent an XML document or fragment...

We just added some new design guidelines related to naming and usage of resources. Enjoy. Resources Resources can be used in libraries to store error messages, labels, and icons. MSDN article Resources and Localization Using the .NET Framework...

Many assume that the Design Guidelines document is intended to be a repository of the best solutions to common API design problems. Let me get it straight right away. This is not the intention at all. The main purpose of the Design Guidelines is to achieve...

Generics is a new feature added to the Whidbey CLR and languages. We are still learning the best way to take advantage of the feature in reusable library APIs. The guidelines below represent out current thinking in this area. 1.0 Generics A new...

The .NET Framework documentation on MSDN has a section describing the design guidelines for managed library developers . The section is based on an internal document that I help to create and maintain. The internal document is being constantly and frequently...