Windows程序绘图示例-优快云博客

本文链接：https://blog.youkuaiyun.com/andylin02/article/details/1551976

本文展示了一个使用Windows API创建窗口并绘制系统信息的简单示例。通过注册窗口类、创建窗口实例、处理消息循环来实现基本的GUI应用程序。特别介绍了如何在窗口中绘制文字并显示系统度量。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

#include <windows.h>
#include <tchar.h>
#include "sysmets.h"

LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR szCmdLine, int nCmdShow)
{
static TCHAR szAppName[] = TEXT("Text test");
HWND hwnd = NULL;
MSG msg = {0};
WNDCLASS wndclass = {0};

//init wndclass
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
wndclass.hIcon  = LoadIcon(NULL, IDI_APPLICATION);
wndclass.hInstance = hInstance;
wndclass.lpfnWndProc = WndProc;
wndclass.lpszClassName = szAppName;
wndclass.lpszMenuName = NULL;
wndclass.style  = CS_HREDRAW | CS_VREDRAW;

//Register class
if (!RegisterClass(&wndclass))
{
  MessageBox(NULL, TEXT("This program require WinNT"),szAppName, MB_ICONERROR);

return 0;
}

hwnd = CreateWindow(szAppName, TEXT("Test for Text 01"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL);

ShowWindow(hwnd, nCmdShow);
UpdateWindow(hwnd);

while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}

return (int)msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static int cxChar = 0;
static int cxCaps = 0;
static int cyChar = 0;

HDC hdc = NULL;
PAINTSTRUCT ps = {0};
TEXTMETRIC tm = {0};

TCHAR szBuffer[10] = "/0";

int i = 0;

switch (message)
{
  case WM_CREATE:
  {
                        hdc = GetDC(hwnd);

   GetTextMetrics(hdc, &tm);
   cxChar = tm.tmAveCharWidth;
   cyChar = tm.tmHeight + tm.tmExternalLeading;
   cxCaps = (tm.tmPitchAndFamily & 1 ? 3 : 2) * cxChar / 2;

   ReleaseDC(hwnd, hdc);
  }
  return 0;

  case WM_PAINT:
  {
   hdc = BeginPaint(hwnd, &ps);

   for (i = 0; i < NUMLINES; i++)
   {
    TextOut(hdc, 0, cyChar * i, sysmetrics[i].szLabel, lstrlen(sysmetrics[i].szLabel));
    TextOut(hdc, 22 * cxCaps, cyChar * i, sysmetrics[i].szDesc, lstrlen(sysmetrics[i].szDesc));

SetTextAlign(hdc, TA_RIGHT | TA_TOP);
TextOut(hdc, 22 * cxCaps + 40 * cxChar, cyChar * i, szBuffer, wsprintf(szBuffer, TEXT("%5d"), GetSystemMetrics(sysmetrics[i].iIndex)));

    SetTextAlign(hdc, TA_LEFT | TA_TOP);
   }
  }
  return 0;

  case WM_DESTROY:
  {
   PostQuitMessage(0);
  }

return 0;
}

return DefWindowProc(hwnd, message, wParam, lParam);
}