win32 窗口 绘制矩形

win32 窗口 绘制矩形

测试环境: win7 64 位 vs2013

建立一个 win32 应用程序 ，空项目，名称是 HelloPaintRect,

在项目中添加源文件 HelloPaintRect.cpp :

内容如下:

#include <windows.h>
#include <stdlib.h>                                                 
#include <string.h>                                                 
#include <tchar.h>                                                  

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
    PSTR szCmdLine, int iCmdShow)
{
    static TCHAR szAppName[] = TEXT("HelloWin");
    HWND         hwnd;
    MSG          msg;
    WNDCLASS     wndclass;

    wndclass.style = CS_HREDRAW | CS_VREDRAW;
    wndclass.lpfnWndProc = WndProc;
    wndclass.cbClsExtra = ;
    wndclass.cbWndExtra = ;
    wndclass.hInstance = hInstance;
    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
    wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    wndclass.lpszMenuName = NULL;
    wndclass.lpszClassName = szAppName;

    if (!RegisterClass(&wndclass))
    {
        MessageBox(NULL, TEXT("This program requires Windows NT!"),
            szAppName, MB_ICONERROR);
        return ;
    }

    hwnd = CreateWindow(szAppName,                  // window class name
        TEXT("The Hello Program"), // window caption
        WS_OVERLAPPEDWINDOW,        // window style
        CW_USEDEFAULT,              // initial x position
        CW_USEDEFAULT,              // initial y position
        CW_USEDEFAULT,              // initial x size
        CW_USEDEFAULT,              // initial y size
        NULL,                       // parent window handle
        NULL,                       // window menu handle
        hInstance,                  // program instance handle
        NULL);                     // creation parameters

    ShowWindow(hwnd, iCmdShow);
    UpdateWindow(hwnd);

    while (GetMessage(&msg, NULL, , ))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    HDC         hdc;
    PAINTSTRUCT ps;

    switch (message)
    {
    case WM_CLOSE:
        DestroyWindow(hwnd);
        break;

    case WM_DESTROY:
        PostQuitMessage();
        break;

    case WM_PAINT:                                            

         hdc = BeginPaint(hwnd, &ps);                          //1

         Rectangle(hdc,,,,);                        // 2

         EndPaint(hwnd, &ps);                                 // 3

         break;                                            

    default:
        return DefWindowProc(hwnd, message, wParam, lParam);

    }

    return ;
}

           

显示效果如下: