Question

I am using a VCL Forms application in C++ Builder.

How do I display a Messagebox with Yes/No/Cancel buttons and then detect if the yes, the no or the cancel button is pressed.

Here is my code:

if(MessageBox(NULL, "Test message", "test title",  MB_YESNOCANCEL) == IDYES) {}

I have included the following:

#include <windows.h>

I am getting the following errors:

E2034 Cannot convert 'char const[13]' to 'const wchar_t *'

E2342 Type mismatch in parameter 'lpText' (wanted 'const wchar_t *', got 'const char *')

Answer 1

You need to use wide characters in the call to MessageBox and you need to store the result in a variable, before working out what to do next.

const int result = MessageBox(NULL, L"Test message", L"test title",  MB_YESNOCANCEL);

switch (result)
{
case IDYES:
    // Do something
    break;
case IDNO:
    // Do something
    break;
case IDCANCEL:
    // Do something
    break;
}

You should read the documentation for MessageBox.