Hello!Expert.I am learning about C Sharp.I bought a book from bookshop.The book's name is <<Professional C#, 3rd Edition>>.As a result,I have faced a lot of difficulties.Now I want to asked a question.What is the mean of the book's sentence?The sentence is at Page 58,it is "Note that we are not permitted to declare a multi-part namespace nested within another namespace."Please give me a example(Code).Thank you!

It appears the book in question is based on .Net 1.1.

What they are saying is:

You CAN do this:

namespace Cheese
{
    namespace MoreCheese
    {
    }
}

But you can NOT do this:

namespace Cheese
{
    namespace Stinky.Cheese
    {
    }
}

If you try to compiled the second one in 1.1 you get this error:

error CS0134: Cannot use qualified namespace names in nested namespace declarations

THIS ONLY APPLIES TO .NET 1.1. .Net 2.0 DOES allow this.

-Peter

Thanks for your relication.
I tried to complie a example in 2.0,I don't get a error,and there is the same sentece in <<Professinal C# 2005>> as <<Professional C#, 3rd Edition>>.

Note that we are not permitted to declare a multi-part namespace nested within another namespace.

I make sure that the book is wrong!

It would seem that the book is incorrect. It's also possible that when the book was written, MS hadn't made this change. Given the amount of time it takes to write a book, it's understandable that changes in the software could be made that affect the accuracy of the book.

-Peter