Windows Form Application Variable Question

[kief12]

I have a class called User. I want to make a User object called myUser that can be access able to both windows forms that i have create. I have main.cpp which calls the creation of the first form

Application::Run(gcnew Form1());

but i can't seem to access the Form1 object it creates. I also tried making a User object in the forms but i got this error

 	private: User myUser;

  error C4368: cannot define 'myUser' as a member of managed 'myProject::w_Name': mixed types are not supported

How do i define variables in the visual c++ forms and execute functions outside of their headers.

[weaknessforcats]

This looks like C#.

Moving this to the .NET forum.

[Plater]

This looks like C#.

Moving this to the .NET forum.

It's C++, but probably .NET constructs

[kief12]

It's C++, but probably .NET constructs

Yeah i am using c++ this is my first time using a gui for c++ so i am lost and confused on what to use. I follow a guide that had me using the windows form application in visual c++. Which brought me here

[TRScheel]

I have a class called User. I want to make a User object called myUser that can be access able to both windows forms that i have create. I have main.cpp which calls the creation of the first form

Application::Run(gcnew Form1());

but i can't seem to access the Form1 object it creates. I also tried making a User object in the forms but i got this error

 	private: User myUser;

  error C4368: cannot define 'myUser' as a member of managed 'myProject::w_Name': mixed types are not supported

How do i define variables in the visual c++ forms and execute functions outside of their headers.

Try

[code=cpp]
private:
User ^myUser;
[/code]

[kief12]

Try

[code=cpp]
private:
User ^myUser;
[/code]

Private: User *myUSer;

Worked thank you

If i wanted to access myUser in the main window of my application from the main function how would i do it?

[TRScheel]

Private: User *myUSer;

Worked thank you

If i wanted to access myUser in the main window of my application from the main function how would i do it?

That is declaring a native pointer, where as with ^ it is within the garbage collection.

[TRScheel]

One of my favorite books has this table describing this

Operator:
Stack / Native Heap
Managed Heap

Address:
&
%

Pointer declaration:
*
^

Dereference:
*
*

Example:
Static/Native Heap
value struct V{ int i; };
V v;
V * pV = &v; v.i;
pV->i;

Managed Heap
ref struct R{ int i; };
R ^r1 = gcnew R();
R ^r2 = %(*r1);
R r;
R ^r3 = %r;
r1->i;
(*r2).i;

[kief12]

That is declaring a native pointer, where as with ^ it is within the garbage collection.

w_Name.h(36) : error C3699: '^' : cannot use this indirection on type 'User'
        compiler replacing '^' with '*' to continue parsing'

Will not let me use ^

[TRScheel]

w_Name.h(36) : error C3699: '^' : cannot use this indirection on type 'User'
        compiler replacing '^' with '*' to continue parsing'

Will not let me use ^

How is User declared?

[TRScheel]

How is User declared?

[CODE=cpp]public class User { .. };[/CODE]

will not work.

You need either

[CODE=cpp]public value class User { ... };[/CODE]

or

[CODE=cpp]public ref class User { .. };[/CODE]

[kief12]

if the main form window is created using Application::Ru n(gcnew Form1()); Who would i run the function lets say myRandomFunctio n() in Form1.h from a different window or the

int main(array<System::String ^> ^args)

[TRScheel]

if the main form window is created using Application::Ru n(gcnew Form1()); Who would i run the function lets say myRandomFunctio n() in Form1.h from a different window or the

int main(array<System::String ^> ^args)

[code=cpp]
public ref class Form1
{
private:
...
public:
Form1();
myRandomFunctio n();
};
[/code]

Declaring it like that should make it accessible else where.

[sawpit]

[code=cpp]
public ref class Form1
{
private:
...
public:
Form1();
myRandomFunctio n();
};
[/code]

Declaring it like that should make it accessible else where.

A newbee here. Can you give an example of the code that would call myRandomFunctio n()? How do you get a reference to Form1 elsewhere, given that the form is gcnew'd directly to Run()? Thanks.

[TRScheel]

A newbee here. Can you give an example of the code that would call myRandomFunctio n()? How do you get a reference to Form1 elsewhere, given that the form is gcnew'd directly to Run()? Thanks.

Dont gcnew it in the Run function, thats the only way that I know of. Although, someone might be able to extract it from the Application object.