Help: Why can't the function in the dynamic library be loaded

soulflayer

Dynamic library code:
extern "C" __declspec (dllexport) HWND __stdcall CreateCW (HWND);
int WINAPI DllEntryPoint (HINSTANCE hinst, unsigned long reason, void * lpReserved)
{
    return 1;
}
// ------------------------------------------------ ---------------------------
HWND __stdcall CreateCW (HWND MainWindowHandle)
{
  Application-> Handle = MainWindowHandle;
  Form2 = new TForm2 (NULL);
  SetParent (Form2-> Handle, MainWindowHandle);
  Form2-> ShowModal ();
  return Form2-> Handle;

}
Calling code:

    HINSTANCE hInstance;
    __showWindow show;
    if (hInstance == NULL)
    {
       hInstance = LoadLibrary ("Project2.dll");
    }
    if (hInstance! = NULL)
    {
     MessageBox (NULL, "BEGIN", "", 0);
     show = (__showWindow) GetProcAddress (hInstance, "CreateCW");
        if (NULL! = show)
       {
            hCwnd = show (Form1-> Handle);
       }
       else
       {
            MessageBox (NULL, "HANSHUJIAZAISHIBAI", "", 0);
       }
    }
    else
    {
        MessageBox (NULL, "Dynamic library loading failed", "", 0);
    }

baiyunyy

GetProcAddress (DLL, "_ CreateCW"); Add a "_".

zx1984104x

There is no problem looking at the code, but I don’t see the definition of the __showWindow function pointer
What is wrong?

soulflayer

Okay, I get it now
  HINSTANCE hInstance;
To be initialized, but now there are new problems, the program runs to
show(Form1->Handle );
The following problem appears
project project1.exe raised exception class EInvalidOperation with message'Cannot make a visible window modal'.process stopped

csb1024

if(NULL != show)
       {
            hCwnd = show(Application->Handle );
       }

zx1984104x

The tips have all said, "Cannot make a visible window modal"
I think it’s the variable name, because "Form2" is a global variable that will be exported when the Form is created
Unless your Form2 is not automatically generated, otherwise Form2 can be used directly without writing new in the code
Try another variable name and try

I think it will be because Form2 already exists, although you have assigned a new instance to Form2. . .