using inside or outside my namespace

[Digital Fart]

I was looking at the GFAX - Gnome fax application and i see
that in the main.cs the author puts the using inside his namespace.

namespace gfax {
using System;
using System.IO;
using System.Collecti ons;
....

But in all the tutorial i have seen they start with using and then
start their namespace.

What would be the difference and/or advantage?

Joeri

[Nicholas Paldino [.NET/C# MVP]]

Joeri,

The using directive can be used in a namespace scope, in which case it
is applicable to the namespace in that file. If it is outside of the
namespace, then it is applicable to the whole file.

For more information, check out section 9.3 of the C# Language
Specification, titled "Using Directives", located at (watch for line wrap):

http://msdn.microsoft.com/library/de...rpspec_9_3.asp

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- ni************* *@exisconsultin g.com

"Digital Fart" <pr*********@an gelfire.com> wrote in message
news:32******** *************** *********@4ax.c om...

I was looking at the GFAX - Gnome fax application and i see
that in the main.cs the author puts the using inside his namespace.

namespace gfax {
using System;
using System.IO;
using System.Collecti ons;
...

But in all the tutorial i have seen they start with using and then
start their namespace.

What would be the difference and/or advantage?

Joeri

[Mike M.]

(Line wrap alert - didn't fix them)
//*************** *************** *********
using System.Text;

namespace ConsoleApp
{
using System.IO;

class Class1
{
[STAThread]
static void Main(string[] args)
{
string strPath =
Directory.GetPa rent("C:\\Docum ents and Settings\\A
User").FullName ;
StringBuilder strBuilder = new
StringBuilder(s trPath);
strBuilder.Appe nd("\\test.xml" );
System.Xml.XmlD ocument objXml =
new System.Xml.XmlD ocument();
objXml.Load(str Path);
}
}
}

namespace ConsoleApp.Test
{
using System.Xml;

public class Class2
{
public Class2()
{
string strPath =
System.IO.Direc tory.GetParent( "C:\\Docume nts and
Settings\\A User").FullName ;
StringBuilder strBuilder = new
StringBuilder(s trPath);
strBuilder.Appe nd("\\test.xml" );
XmlDocument objXml = new
XmlDocument();
objXml.Load(str Path);
}
}
}

//*************** *************** *************** ******

-----Original Message-----
I was looking at the GFAX - Gnome fax application and i seethat in the main.cs the author puts the using inside his namespace.
namespace gfax {
using System;
using System.IO;
using System.Collecti ons;
....

But in all the tutorial i have seen they start with using and thenstart their namespace.

What would be the difference and/or advantage?

Joeri
.

[Grant Richins [MS]]

In addition to what everybody else has pointed out, it also affects name
lookup. When the using clauses are inside the namespace, they will be
searched before the outer namespace is searched. When the using clauses are
outside the namespace, they will be searched after.

Example:
// file1.cs
namespace N1 {
namespace N2 {
class C1 { ... }
}
}
class C1 { ... }

// file2.cs
using N1.N2;
namespace N1 {
// Any code here that references C1 in here will get the outer C1
}

// file2.cs
namespace N1 {
using N1.N2;
// Any code here that references C1 in here will get N1.N2.C1
}

--
--Grant
This posting is provided "AS IS" with no warranties, and confers no rights.
"Digital Fart" <pr*********@an gelfire.com> wrote in message
news:32******** *************** *********@4ax.c om...

I was looking at the GFAX - Gnome fax application and i see
that in the main.cs the author puts the using inside his namespace.

namespace gfax {
using System;
using System.IO;
using System.Collecti ons;
...

But in all the tutorial i have seen they start with using and then
start their namespace.

What would be the difference and/or advantage?

Joeri