Issue on creating window with concanated string

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#include <windows.h>
#include <iostream>
#include <string>
#include <cstdlib>
#include <fstream>

/* This is where all the input to the window goes to */
LRESULT CALLBACK WndProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam) {
	int ID_BUTTON = 13;

	switch(Message) {
				
		case WM_CREATE:{
			HWND boutton = CreateWindow("button","Click!",WS_VISIBLE|WS_CHILD|BS_FLAT|BS_CENTER,100,100,50,30,hwnd,(HMENU) 13,NULL,NULL);
			break;
		}
	
		case WM_COMMAND:{
			switch (LOWORD(wParam)){
				case 13:
					std::string phrase = std::string("simple")+std::string(" ")+std::string("string");
					CreateWindowEx(std::string("STATIC"),phrase,WS_VISIBLE|WS_CHILD|WS_BORDER,200,200,100,100,hwnd,NULL,NULL,NULL);
			}
			break;
		} 
	
		
		/* Upon destruction, tell the main thread to stop */
		case WM_DESTROY: {
			PostQuitMessage(0);
			break;
		}
		
		/* All other messages (a lot of them) are processed using default procedures */
		default:
			return DefWindowProc(hwnd, Message, wParam, lParam);
	}
	return 0;
}

/* The 'main' function of Win32 GUI programs: this is where execution starts */
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
	WNDCLASSEX wc; /* A properties struct of our window */
	HWND hwnd; /* A 'HANDLE', hence the H, or a pointer to our window */
	MSG msg; /* A temporary location for all messages */

	/* zero out the struct and set the stuff we want to modify */
	memset(&wc,0,sizeof(wc));
	wc.cbSize		 = sizeof(WNDCLASSEX);
	wc.lpfnWndProc	 = WndProc; /* This is where we will send messages to */
	wc.hInstance	 = hInstance;
	wc.hCursor		 = LoadCursor(NULL, IDC_ARROW);
	
	/* White, COLOR_WINDOW is just a #define for a system color, try Ctrl+Clicking it */
	wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
	wc.lpszClassName = "WindowClass";
	wc.hIcon		 = LoadIcon(NULL, IDI_APPLICATION); /* Load a standard icon */
	wc.hIconSm		 = LoadIcon(NULL, IDI_APPLICATION); /* use the name "A" to use the project icon */

	if(!RegisterClassEx(&wc)) {
		MessageBox(NULL, "Window Registration Failed!","Error!",MB_ICONEXCLAMATION|MB_OK);
		return 0;
	}

	hwnd = CreateWindowEx(WS_EX_CLIENTEDGE,"WindowClass","Caption",WS_VISIBLE|WS_OVERLAPPEDWINDOW,
		CW_USEDEFAULT, /* x */
		CW_USEDEFAULT, /* y */
		640, /* width */
		480, /* height */
		NULL,NULL,hInstance,NULL);
		
	
	/*  Pointer not needed.
	CreateWindow("Button1","Click Me!",WS_TABSTOP|WS_VISIBLE|WS_CHILD,250,250,100,100,hwnd,NULL,(HINSTANCE)GetWindowLongPtr(hwnd,GWLP_HINSTANCE),NULL);
	
	case WM_COMMAND:{
		switch (LOWORD(wParam)){
			case ID_BUTTON:
				MessageBox(hwnd,"Hello World!","Tap Here To Add Text",MB_OK|MB_ICONINFORMATION);
		}
		break;
	} 
	
	if(hwnd == NULL) {
		MessageBox(NULL, "Window Creation Failed!","Error!",MB_ICONEXCLAMATION|MB_OK);
		return 0;
	}

	*/
	/*
		This is the heart of our program where all input is processed and 
		sent to WndProc. Note that GetMessage blocks code flow until it receives something, so
		this loop will not produce unreasonably high CPU usage
	*/
	while(GetMessage(&msg, NULL, 0, 0) > 0) { /* If no error is received... */
		TranslateMessage(&msg); /* Translate key codes to chars if present */
		DispatchMessage(&msg); /* Send it to WndProc */
	}
	return msg.wParam;
}


to be specific, on line 22 the program outputs:

[Error] cannot convert 'std::string {aka std::basic_string<char>}' to 'DWORD {aka long unsigned int}' for argument '1' to 'HWND__* CreateWindowExA(DWORD, LPCSTR, LPCSTR, DWORD, int, int, int, int, HWND, HMENU, HINSTANCE, LPVOID)'


keep in mind im using DEV C++.
Last edited on
CreateWindowEx() expects as first parameter a DWORD, but in line 22 you provide as first parameter an std::string, so the problem is quite literally what the error message says.
Last edited on
What are you trying to do in your button handler case (WM_COMMAND->case 13)? Trying to show the user clicked the button?

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   case WM_COMMAND:
      switch (LOWORD(wParam))
      {
      case 13:
         MessageBox(NULL, "The Button Was Pressed!", "Test!", MB_OK);
      }
      break;

A message box works wonders when informing the user of simple information. No need to go to the effort of creating a custom dialog box.
Last edited on
Passing std::string to CreateWindowEx? Don't you get a compiler error?
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