http://blogs.msdn.com/b/erickt/archive/2006/09/12/751406.aspxExtension methods are one of the many great new features of C# 3.0. They basically allow you to declare static methods that appear to be instance methods of a type, even if you have no access to the type (sealed classes, etc). The key point is that youen-USTelligent Evolution Platform Developer Build (Build: 5.6.50428.7875)http://blogs.msdn.com/b/erickt/archive/2006/09/12/751406.aspx#4313848Fri, 10 Aug 2007 00:38:43 GMT91d46819-8472-40ad-a661-2c78acb4018c:4313848MSDNArchive<p>Ed,</p> <p>The rules basically say that the one in the &quot;closest&quot; namespace to you gets called. If two methods are the same distance away, then you should get a compiler error. All part of the learning curve around these new techniques...</p> <p>Thanks,</p> <p>Erick</p><div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=4313848" width="1" height="1">http://blogs.msdn.com/b/erickt/archive/2006/09/12/751406.aspx#4310198Thu, 09 Aug 2007 15:50:43 GMT91d46819-8472-40ad-a661-2c78acb4018c:4310198Ed<p>What about ambiguous extensions? You make one called 'In' and a developer gets it via a using statement (e.g. using EricksExtensions)</p> <p>I make an extension called 'In' and a developer wants to use that also.</p> <p>(e.g. using EdsExtensions)</p> <p>obj.In is now ambiguous.</p> <p>How to tell the which one to resolve?</p><div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=4310198" width="1" height="1">http://blogs.msdn.com/b/erickt/archive/2006/09/12/751406.aspx#751609Wed, 13 Sep 2006 08:30:55 GMT91d46819-8472-40ad-a661-2c78acb4018c:751609Humble Abode&amp;amp;quot;Extension methods are one of the many great new features of C# 3.0. They basically allow you to<img src="http://blogs.msdn.com/aggbug.aspx?PostID=751609" width="1" height="1">