how to call a window form from existing c program?

[jenuel]

I have an existing project using c/c++ .NET. Currently I have been given a task to create a windows form from my existing code.
So i have add new project windows form application in the existing c/c++ projects.form.h, form.cpp has been automatically created.
Now I am having problem to call the window from my c files.
Even i could not call the form.h file from my c program.
Is there any solution for this problem.
Listed here is the coding....

login.c
int LoginMain(int eid,int task)
{
//typedef depanV5;
LoginClearOtherScreens();
LoginEntry(eid,task);
// this flag is set to 0 in RepScrInitDisplay called LoginEntry
dp_in_logscr = 1;
RepScrScan();

//I WOULD LIKE TO CALL THE FORM AT THIS STAGE

CashierPopUp();
dp_in_logscr = 0;
LoginExit();
if (!isatty (fileno (stdout)))
{
//printf ("#########################################\nHERE I AM \n#########################################\n");
printf ("operation: %d, operation2: %d, operator: %d, supervisor_id: '%s'\n",operation,operation2,Operator,supervisor_id);
}
return(0);
}


form.cpp
[STAThreadAttribute]
int main(array<System::String ^> ^args)
{
// Enabling Windows XP visual effects before any controls are created
Application::EnableVisualStyles();
Application::SetCompatibleTextRenderingDefault(false);

// Create the main window and run it
Application::Run(gcnew Form1());
return 0;
}