Namespace with 2 forms - winforms

Question

I have namespace "Client" with form MainWindow and form MyForm
MainWindow creates MyForm.
MainWindow.h
#pragma once
namespace Client {
using namespace System;
using namespace System::ComponentModel;
using namespace System::Collections;
using namespace System::Windows::Forms;
using namespace System::Data;
using namespace System::Drawing;
public ref class MainWindow : public System::Windows::Forms::Form
{
public:
MainWindow(void)
{
InitializeComponent();
}
....
....
....
}
in MyForm.h i write this:
#pragma once
namespace Client {
using namespace System;
using namespace System::ComponentModel;
using namespace System::Collections;
using namespace System::Windows::Forms;
using namespace System::Data;
using namespace System::Drawing;
public ref class MyForm : public System::Windows::Forms::Form
{
private:
MainWindow ^f; //this is my problem
public:
MyForm(void)
{
InitializeComponent();
}
......
......
......
}
After compile, i have this error in line MainWindow ^f;:
1>c:\users\user\desktop\testlist\client\MyForm.h(17): error C2143: syntax error : missing ';' before '^'
1>c:\users\user\desktop\testlist\client\MyForm.h(17): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1> MyForm.cpp
If i write this Client::MainWindow ^f;:
1>c:\users\user\desktop\testlist\client\MyForm.h(17): error C2039: 'MainWindow' : is not a member of 'Client'
1>c:\users\user\desktop\testlist\client\MyForm.h(17): error C2143: syntax error : missing ';' before '^'
1>c:\users\user\desktop\testlist\client\MyForm.h(17): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1> MainWindow.cpp
1 errror - The form is a member of Client, why?
if add #include "MainWindow.h", errors are on MainWindow ^f;:
1>c:\users\user\desktop\testlist\client\MyForm.h(19): error C2143: syntax error : missing ';' before '^'
1>c:\users\user\desktop\testlist\client\MyForm.h(19): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1> MainWindow.cpp
How can i fix this problem?
______________________________Update for ArnonZilca
Myform - its a ref class, so i use ref struct and instead of mreoer myvar; i write mreoer ^myvar;
Errors in mreoer ^myvar; :
1>c:\users\user\desktop\testlist\client\MyForm.h(20): error C2143: syntax error : missing ';' before '^'
1>c:\users\user\desktop\testlist\client\MyForm.h(20): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\users\user\desktop\client\client\MyForm.h(155): error C2227: left of '->Print' must point to class/struct/union/generic type
1> MainWindow.cpp
_________________________________UPDATE
So in Myform.h i write this:
#pragma once
namespace Client {
ref class MainWindow;
using namespace System;
using namespace System::ComponentModel;
using namespace System::Collections;
using namespace System::Windows::Forms;
using namespace System::Data;
using namespace System::Drawing;
public ref class MyForm : public System::Windows::Forms::Form
{
private:
MainWindow ^f; //this is my problem
public:
MyForm(void)
{
InitializeComponent();
}
......
......
......
}
and if i use this variable (^f) in MyForm.h i have this errors on line where i using it:
\users\user\desktop\client\client\MyForm.h(155): error C2027: use of undefined type 'Client::MainWindow'
1> c:\users\user\desktop\client\client\MyForm.h(8) : see declaration of 'Client::MainWindow'
MainWindow have public method void Print () { cout << "HEY" << endl; }
In MyForm.h i do this: f->Print();

Answer 1

This tends to be a bit rough on programmers that are used to more recent languages. But this is normal kind of problem to have, C++/CLI inherits the compilation model of the C++ language. It is a single-pass compiler, all definitions must be known before you can use them. A model that dates from the previous century, back when 64KB of RAM fit in shoebox and cost an arm and three legs.
Technically it isn't quite that bad, C++ is more like a 1.5 pass compiler. You can refer ahead to class members inside inline function definitions. Which doesn't exactly help to diagnose this kind of problem :)
But you must do the C++ dance here, your MyForm.h file can contain a forward declaration, ref class MainWindow; gets that done. But any code that dereferences members of f must only appear in MyForm.cpp file. That .cpp file can #include both MyForm.h and MainWindow.h so all type definitions are available. And yes, that does mean that you may well have to move methods that were added by the designer from the .h file to the .cpp file. Do not panic, it's normal.

Answer 2

It seems you forgot to include the header where Client::MainWindow is defined