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Implementing collections by inhereting List a bad practice?

Posted By:      Posted Date: September 20, 2010    Points: 0   Category :ASP.Net
Hi All,
I once read an article by Imaar Spaanjars on how to build 3 tier applications. (http://imar.spaanjaars.com/416/building-layered-web-applications-with-microsoft-aspnet-20-part-1) which has formed the basis of my coding for a while now.
Thus I implement collections as he has done, by inheriting a List. So if I have a class named Employee,to implement a collection I will also have a class Employees as below.
class Employee

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