Thread: Using String Arrays & Pointers in a Win32 App

Hello

I wish to know how to write a string array in a Win32 Application, not a console application.
In a console app, I would use the following code:

Code:

#include <iostream>
#include <string>
using namespace std;

int main()
{
  std::string conversation[2] = {"hi","bye"};
  cout<< conversation[0] <<endl;
  cout<< conversation[1] <<endl;
}

This would first show "hi" on one line, and "bye" on the other.
0 would point to "hi", 1 would point to "bye".


In the Win32 app, however, I have trouble using this method.
Looking at the menu portion of WndProc :

Code:

switch (message)
{
  case WM_COMMAND:
  {
    wmId    = LOWORD(wParam);
    wmEvent = HIWORD(wParam);
    switch (wmId)
    {
      case IDM_ABOUT:
     	::MessageBox(hWnd , _T("Message") , _T("Title") , MB_OK);
     	break;
      case IDM_EXIT:
     	DestroyWindow(hWnd);
     	break;
    }

Focusing on the About section of the menu,
if I do it this way, using the _T("") macro, it does work.
When I try using the same string array & pointer method as I do in console programming, I get errors.
My goal is to have something along the lines of:

Code:

switch (message)
{
  case WM_COMMAND:
  {
    wmId    = LOWORD(wParam);
    wmEvent = HIWORD(wParam);
    std::string conversation[2] = {"hi" , "bye"};
    switch (wmId)
    {
      case IDM_ABOUT:
     	::MessageBox(hWnd , conversation[0] , conversation[1] , MB_OK);
     	break;
      case IDM_EXIT:
     	DestroyWindow(hWnd);
     	break;
    }

I've tried using the wchar_t datatype instead. It works when I use it alone, such as in:

Code:

switch (message)
{
  case WM_COMMAND:
  {
    wmId    = LOWORD(wParam);
    wmEvent = HIWORD(wParam);
    wchar_t conversation[] = L"Hi";
    switch (wmId)
    {
      case IDM_ABOUT:
     	::MessageBox(hWnd , conversation , _T("Title") , MB_OK);
     	break;
      case IDM_EXIT:
     	DestroyWindow(hWnd);
     	break;
    }

However, I don't know how to make wchar_t arrays.
When I try to make something along the lines of an array:

Code:

switch (message)
{
  case WM_COMMAND:
  {
    wmId    = LOWORD(wParam);
    wmEvent = HIWORD(wParam);
    wchar_t conversation[] = {L"Hi",L"Bye"};
    switch (wmId)
    {
      case IDM_ABOUT:
     	::MessageBox(hWnd , conversation[0] , _T("Title") , MB_OK);
     	break;
      case IDM_EXIT:
     	DestroyWindow(hWnd);
     	break;
    }

I get the following error message:
error C2664: 'MessageBoxW' : cannot convert parameter 2 from 'wchar_t' to 'LPCWSTR'

Does anyone know how to use strings as one would in a console application?
Compiler is Visual C++ 2008 Express Edition
Thanks in advance

By having the L before "Hi" and "Bye", I get this error:
error C2117: 'conversation' : array bounds overflow
When I removed the L's, that error was gone.
I think this has to do with the amount of bits being used to represent this string - I know Unicode offers much much more than ANSI - which would explain it.
I'm going for Unicode as much as I can for this reason.

When I wrote it as:
wchar_t conversation[2][] = {"Hi","Bye"};
I got:
error C2087: 'conversation' : missing subscript

I then changed it to
wchar_t conversation[][2] = {"Hi","Bye"};
to see if it was notational. It removed the error.
The only error I have now is:
error C2440: 'initializing' : cannot convert from 'const char [3]' to 'wchar_t'
along with
There is no context in which this conversion is possible
(How encouraging...)

and the last error I get is
error C2228: left of '.c_str' must have class/struct/union


Does anyone know how to otherwise index strings in a Win32 App?
I will always try to solve my own problems as much as I can - but I can only do so much with logic when it's a language/notational issue - I either know it or I don't

Thank you everyone for your input

Thank you everyone.

My first try was to use std::string before trying the array of character arrays.
The reason it didn't work is because I didn't know about .c_str() .
I was also "using namespace std;" which works for consoles but not in windows apparently.

Yeah the main problem is that I'm still learning right now.
Silent successes are bound to happen, but I'm acquiring new bits of useful information which helps me piece information together more coherently.

There are very few differences between console mode apps and Win32 apps aside from the apparent Win32 API calls and Win32 data types that will be in the Win32 app. The main function looks a bit different and the assembly startup code will be looking for a different signature for main in Win32 and console mode.

From a purely C++ standpoint though there are nearly no differences between these two types of applications.