程式語言 - MinGW - C/C++ - Painting - Draw Text


參考資訊：
http://www.winprog.org/tutorial/
http://winapi.freetechsecrets.com/win32/
https://github.com/gammasoft71/Examples_Win32
http://masm32.com/board/index.php?topic=3584.0
https://learn.microsoft.com/en-us/windows/win32/winmsg/window-styles

使用TextOut()顯示文字時，只有X、Y參數可以用來設定顯示的位置，當文字長度超過顯示區域時，就需要拆解文字，包含置中顯示也是需要花費額外的計算，如果遇到這些問題，建議使用DrawText()顯示文字，DrawText()提供更多選項使用，包含多行顯示、置中顯示，使用者只需要傳入顯示範圍即可

main.c

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#include <stdbool.h>
#include <windows.h>
  
HWND hWin = NULL;
WNDPROC defWndProc = NULL;
  
LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    HDC hdc = NULL;
    HFONT font = NULL;
    PAINTSTRUCT ps = {0};
    const char *pMsg = "Test";
 
    switch (uMsg) {
    case WM_CLOSE:
        DestroyWindow(hWnd);
        return 0;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    case WM_PAINT:
        hdc = BeginPaint(hWnd, &ps);
        font = CreateFont(48, 0, 0, 0, FW_BOLD, false, false, false, 0,
           OUT_OUTLINE_PRECIS, CLIP_DEFAULT_PRECIS,
           CLEARTYPE_QUALITY, DEFAULT_PITCH | FF_DONTCARE, "Arial");
 
        SetTextColor(hdc, RGB(0x00, 0x00, 0xff));
        SetBkMode(hdc, TRANSPARENT);
        SelectObject(hdc, font);
        DrawText(hdc, pMsg, strlen(pMsg), &ps.rcPaint, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
        EndPaint(hWnd, &ps);
        DeleteObject(font);
        break;
    }
    return CallWindowProc(defWndProc, hWnd, uMsg, wParam, lParam);
}
  
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    hWin = CreateWindow(WC_DIALOG, "main",
        WS_OVERLAPPEDWINDOW | WS_VISIBLE, 0, 0, 300, 300, NULL, NULL, NULL, NULL);
    defWndProc = (WNDPROC)SetWindowLongPtr(hWin, GWLP_WNDPROC, (long int)WndProc);
  
    MSG msg = {0};
    while (GetMessage(&msg, NULL, 0, 0)) {
        DispatchMessage(&msg);
    }
    ExitProcess(0);
    return 0;
}

Line 30：使用DrawText()顯示文字

編譯、執行 

$ i686-w64-mingw32-gcc -mwindows main.c -o main.exe
$ wine ./main.exe