Referencing namespaces globally?

Question

Is there a way to reference a namespace globally across the whole solution?

So instead of having these lines in every code file:

using System;
using MyNamespace;

having to declare them only once, and every code file would use them.

Btw I am using Visual Studio.

Answer 1

No, this is not possible.

If you're using ReSharper, you can set an option to include specific using directives in every new file you create though.

Answer 2

No, C# doesn't have this concept. Each source file is independent in this respect. (And if the using directives are in a namespace declaration, those are independent from other using directives in peer namespace declarations, too. That's a pretty rare case though in my experience.)

You don't need ReSharper to change what gets included in a new class though. You can use the Visual Studio templates.

EDIT: Just to clarify the point about using directives within namespaces, suppose we had (all in one file):

using Foo;

namespace X
{
    using Bar;
    // Foo and Bar are searched for code in here, but not Baz
}

namespace Y
{
    using Baz;
    // Foo and Baz are searched for code in here, but not Bar
}

Usually I only have one namespace declaration in a file, and put all the using directives before it.

Answer 3

From this SO question and follow-up blog post. You can edit the Visual Studio default templates.

To do this, look at the file in this zip : [Program Files][Visual Studio]\Common7\IDE\ItemTemplates\CSharp\Code\1033\Class.zip

and modify the Class.cs file as needed. Additionally, Visual Studio may have cached this file here : [Program Files][Visual Studio]\Common7\IDE\ItemTemplatesCache\CSharp\Code\1033\Class.zip

Answer 4

As others have mentioned Visual Studio Templates are the way to go.

Note that simply adding a using statement to your template will not ensure that the compiler can resolve your types. So, if you are adding a using statement for MyNamespace in every class you may need to add an assembly reference to your project as well. See the C# FAQ for more information.