Should 'using' be inside the namespace or outside? [duplicate]

Question

Possible Duplicate:
Should Usings be inside or outside the namespace

Are there any technical reasons for preferring this

namespace Foo
{
     using System;
     using System.IO;

instead of the default

using System;
using System.IO;

namespace Foo
{

Answer 1

Eric Lippert explains this.

In general, they're identical.
However, using statements in the namespace can see namespaces and aliases included outside the namespace.