Placing using before namespace{} or in namespace{} - What's the difference?

[Empire City]

Can someone tell me what is the difference in placing the using in the
namespace{} and before the namespace{} ?

namespace MyProj
{
using System;
using System.Web;
}

using System;
using System.Web;
namespace MyProj
{
}

 

[Joe Mayo]

Hi Empire,

Comments in-line.

Can someone tell me what is the difference in placing the using in the
namespace{} and before the namespace{} ?

namespace MyProj
{
using System;
using System.Web;
}

Here the using statements only apply to the code within the block defined by
MyProj. If you added another namespace to the same file, like this:

namespace MyOtherProj
{
class MyClass { Int32 myInt; }
}

You would get a compiler error "The type or namespace Int32 could not be
found...".

using System;
using System.Web;
namespace MyProj
{
}

On this one, the using statements apply to all code in this file. For
example, if I defined:

namespace MyOtherProj
{
}

in the same file, I wouldn't need to re-define the using statements.

I suppose if someone felt a need to define multiple namespaces in the same
file, the second format would be useful.

Joe

 

[Empire City]

OK, thank you. Makes perfect sense now. I think what threw me off was the
Duwamish example puts the using within the namespace, while when you create
a web form the usings are above the namespace.

--