Namespace around API calls

[David A]

I'm trying to "isolate" some unmanaged calls to DLLs in a separate namespace
so I can have all the unmanaged calls to DLL functions in a separate module
and then these can be called from any other module using the "Imports"
statement. But I can't get it to work, at least not in the manner that I'd
prefer.

You can call the functions using the fully-qualified name, e.g.
"MySpecial.Unma nagedCode.MyFun ction". But I want to be able to work in a
similar manner to the the third test below and call the functions without
having to do this, i.e. just call the function MyFunction() directly in my
main code. This approach works fine if you have a proper class, and
Intellisense "sort of" seems to be seeing the namespace and functions names,
but it won't compile. Any suggestions?

Example:-
FIRST TEST - TWO SIMPLE MODULES
-- WORKS OK
Module Module1
Sub Main()
'Do equivalent of MsgBox("Hello World") using Win32 API
MessageBox(vbNu llString, "Hello world", "MessageBox ", 0)
End Sub
End Module

Module Module2
Public Declare Function MessageBox Lib "user32" Alias "MessageBox A"
(ByVal hWnd As Integer, ByVal lpText As String, ByVal lpCaption As String,
ByVal wType As Integer) As Integer
End Module

SECOND TEST - put win32 function in a namespace, call with full dotted name
-- WORKS OK
Module Module1
Sub Main()
MyWin32Namespac e.MessageBox(vb NullString, "Hello world",
"MessageBox ", 0)
End Sub
End Module

Namespace MyWin32Namespac e
Module Module2
Public Declare Function MessageBox Lib "user32" Alias "MessageBox A"
(ByVal hWnd As Integer, ByVal lpText As String, ByVal lpCaption As String,
ByVal wType As Integer) As Integer
End Module
End Namespace

THIRD TEST - try to Import namespace to avoid having to use the
fully-qualified name each time
-- FAILS
Imports MyWin32Namespac e
Module Module1
Sub Main()
MessageBox(vbNu llString, "Hello world", "MessageBox ", 0)
End Sub
End Module

Module1.vb(1): Namespace or type 'MyWin32Namespa ce' for the Imports
'MyWin32Namespa ce' cannot be found.
Module1.vb(5): Name 'MessageBox' is not declared.

[Mattias Sjögren]

>Module1.vb(1 ): Namespace or type 'MyWin32Namespa ce' for the Imports

'MyWin32Namesp ace' cannot be found.
Module1.vb(5 ): Name 'MessageBox' is not declared.

Check your project properties if you have a root namespace set.
Assuming you have a root namespace of MyProject, you have to change
the imports statement to

Imports MyProject.MyWin 32Namespace
Mattias

--
Mattias Sjögren [C# MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

[AMercer]

> I'm trying to "isolate" some unmanaged calls to DLLs in a separate namespace

so I can have all the unmanaged calls to DLL functions in a separate module
and then these can be called from any other module using the "Imports"
statement. But I can't get it to work, at least not in the manner that I'd
prefer.

What you are trying is ok by me, but FYI Fxcop disapproves. They want you
to put all unmanaged declares in one of the native method classes
(NativeMethods, SafeNativeMetho ds, UnsafeNativeMet hods). They discuss some
rules about these classes. The consequence is that you would always have to
qualify the api call like NativeMethods.B itBlt(...), and that defeats the
purpose of your inquiry in the first place. Just an FYI about an Fxcop style
rule.

[Herfried K. Wagner [MVP]]

"AMercer" <AM*****@discus sions.microsoft .com> schrieb:

I'm trying to "isolate" some unmanaged calls to DLLs in a separate
namespace
so I can have all the unmanaged calls to DLL functions in a separate
module
and then these can be called from any other module using the "Imports"
statement. But I can't get it to work, at least not in the manner that
I'd
prefer.

What you are trying is ok by me, but FYI Fxcop disapproves. They want you
to put all unmanaged declares in one of the native method classes
(NativeMethods, SafeNativeMetho ds, UnsafeNativeMet hods). They discuss
some
rules about these classes.

ACK:

<URL:http://blogs.msdn.com/brada/articles/361363.aspx>
-> "Naming Conventions"

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://classicvb.org/petition/>

[David A]

"Mattias Sjögren" <ma************ ********@mvps.o rg> wrote in message
news:eh******** ******@TK2MSFTN GP12.phx.gbl...

Module1.vb(1 ): Namespace or type 'MyWin32Namespa ce' for the Imports
'MyWin32Namesp ace' cannot be found.
Module1.vb(5 ): Name 'MessageBox' is not declared.

Check your project properties if you have a root namespace set.
Assuming you have a root namespace of MyProject, you have to change
the imports statement to

Imports MyProject.MyWin 32Namespace
Mattias

--
Mattias Sjögren [C# MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

Mattias,

Thank you. That works perfectly.