What are the uses of “using” in C#?

Question

User kokos answered the wonderful Hidden Features of C# question by mentioning the using keyword. Can you elaborate on that? What are the uses of

Answer 1

You can make use of the alias namespace by way of the following example:

using LegacyEntities = CompanyFoo.CoreLib.x86.VBComponents.CompanyObjects;

This is called a using alias directive as as you can see, it can be used to hide long-winded references should you want to make it obvious in your code what you are referring to e.g.

LegacyEntities.Account

instead of

CompanyFoo.CoreLib.x86.VBComponents.CompanyObjects.Account

or simply

Account   // It is not obvious this is a legacy entity