Namespaces and subnamespaces in C#

c#, namespaces

Solution

Because nested namespaces are not included with parent one. See using directive documentation for details

A using directive does not give you access to any namespaces that are nested in the namespace you specify.

Problem

begginers question about C#. In every program I have to include several namespaces, like: ``` using System; using System.Collections.Generic; using System.Linq; using System.Text; ``` Why do I have to include: ``` using System.Collections.Generic; using System.Linq; using System.Text; ``` ... since they are included with first one: ``` using System; ``` Thank you in advance!

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