System namespace(s) problem

[Herby]

I seem to be having a problem with System namespace.
There seem to two System namepaces when viewing through Object browser
within .NET 2005.
One global System::
Then one under <mscorlib>

Each is different, having different sets of classes and some in common.
Why is this?

My project needs to reference the ones from <mscorlib> and not the
other.
How do i correct this?

[Herby]

Ok i understand now that namespaces are shared across system.dll and
mscorlib.dll etc
E.g.

System::Collect ions::

Where a namespace is shared each will have a unique set of classes(I
assume) why has it been split like this?

My problem my project does not seem to have full access to all the
classes in each
For example I am unable to reference

System::Diagnos tics::Debug::As sert( mKeys.Count == mValues.Count );

error C3083: 'Debug': the symbol to the left of a '::' must be a type

This is defined in mscorlib.dll

But am referencing List<T>

also defined in mscorlib.dll

Whats going on here?

[Carl Daniel [VC++ MVP]]

Herby wrote:

Ok i understand now that namespaces are shared across system.dll and
mscorlib.dll etc
E.g.

System::Collect ions::

Where a namespace is shared each will have a unique set of classes(I
assume) why has it been split like this?

My problem my project does not seem to have full access to all the
classes in each
For example I am unable to reference

System::Diagnos tics::Debug::As sert( mKeys.Count == mValues.Count );

System.Diagnost ics is in System.dll, not mscorlib.dll.

The main help topic for each class lists the assembly where the class is
defined, so there's no need to guess or hunt.

-cd

[Herby]

Where is List<T> defined?

What if i want to use classes from mscorlib.dll am i then expected to
do the following:
#import<mscorli b.dll>

Is this being secrectly done for System.dll too?

Im also having another problem:

CString mfc_str("Hello .NET");

// I have to qualify this due to another lib without a namespace having
a String class

System::String^ man_str = gcnew System::String( mfc_str);

I get the following error:

error C2440: 'initializing' : cannot convert from 'CString' to
'wchar_t'
No user-defined-conversion operator available that can perform this
conversion, or the operator cannot be called

If i pass the MFC string to another module as a parameter and inside do
the same conversion then its fine!
In another dummy project with MFC this conversion is fine without
parameter passing.

What is the problem?

[Carl Daniel [VC++ MVP]]

Herby wrote:

Where is List<T> defined?
RTFM, man...

What if i want to use classes from mscorlib.dll am i then expected to
do the following:
#import<mscorli b.dll>
No you don't. You want to

#using <mscorlib.dll >

Is this being secrectly done for System.dll too?
No, you need to

#using <system.dll>
Im also having another problem:

I can't help you with MFC problems. Hopefully someone else will respond to
that part.

-cd

[Herby]

Something is wrong
Why would i get the following error

error C3225: generic type argument for 'TKey' cannot be 'System::Char
^', it must be a value type or a handle to a reference type

When i have the following declaration:

Dictionary<Syst em::String^, RuntimeMap^> mMap;

[Holger Grund]

"Herby" <pr********@gma il.com> wrote

Something is wrong
Why would i get the following error

error C3225: generic type argument for 'TKey' cannot be 'System::Char
^', it must be a value type or a handle to a reference type
Char^ is not a value type, but a boxed value type. System::Char is
the name of the value type (or only char)
When i have the following declaration:

Dictionary<Syst em::String^, RuntimeMap^> mMap;

The error message doesn't make sense for that declaration.
Are you sure you've quoted the correct line of code?

-hg

[Holger Grund]

"Holger Grund" <ho**********@r emove.ix-n.net> wrote

Char^ is not a value type, but a boxed value type. System::Char is
the name of the value type (or only char)

Actually, that should be wchar_t not char.

-hg

[Holger Grund]

"Herby" <pr********@gma il.com> wrote

Im also having another problem:

CString mfc_str("Hello .NET");

// I have to qualify this due to another lib without a namespace having
a String class

System::String^ man_str = gcnew System::String( mfc_str); AFAICT, that should work just fine.

As I understand, this should call the String::String( signed char* ) ctor
(assuming you're not compiling with /D_UNICODE, in which case
the wchar_t* overload would be selected).
CString has a conversion to const char* which should be OK for
the conversion.

I get the following error:

error C2440: 'initializing' : cannot convert from 'CString' to
'wchar_t'
No user-defined-conversion operator available that can perform this
conversion, or the operator cannot be called

That doesn't make sense. It sounds like you're using a ctor overload
with more than one parameter. In that case the first argument type is
a wchar_t for all overloads.

Are you sure, that this is the exact source line and the full diagnostic
message?

-hg

[Herby]

Thanks Holger.

I can assure you i am showing you the right lines of code.
I know it does not make sense, something else is causing these
problems, my hunch is its something to do with the include files.
If i compile the class containing these data members then compiles
fine.
If i compile a client of this class then thats when i get the errors.
Before i went into a painstaking lenghty investigation, i just wondered
if anyone had a 'quick' get out.

I can get around this for the moment via using the following:

ArrayList mKeys;
List<RuntimeMap ^> mValues;

Rather than using the much more expressive:

Dictionary<Stri ng^, RuntimeMap^> mMap;