vc++写的简单图形操作

#include <windows.h> #include "resource.h" #include "Graph.h" #include "Line.h" #include "Ellipse.h" #include <vector> using namespace std; LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM); int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) { static TCHAR szAppName[]=TEXT("SimpleWin"); static TCHAR szClassName[]=TEXT("SimpleWinClass"); HWND hwnd; MSG msg; WNDCLASS wndclass; wndclass.style=CS_HREDRAW|CS_VREDRAW; wndclass.lpfnWndProc=WndProc; wndclass.cbClsExtra=0; wndclass.cbWndExtra=0; 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=szClassName; if(!RegisterClass(&wndclass)) { MessageBox(NULL,TEXT("This program requires Windows NT!"),szAppName,MB_ICONERROR); return 0; } hwnd=CreateWindow(szClassName, TEXT("SimpleWindow"), 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 msg.wParam; } LRESULT CALLBACK WndProc(HWND hWnd,UINT message,WPARAM wParam,LPARAM lParam) { HDC hdc; PAINTSTRUCT ps; HMENU hMenu; static int flag; static vector<CGraph*> myGraph; vector<CGraph*>::iterator iter; static POINT ptStart, ptEnd; CGraph *p; switch(message) { case WM_LBUTTONDOWN: ptStart.x = LOWORD(lParam); ptStart.y = HIWORD(lParam); break; case WM_LBUTTONUP: ptEnd.x = LOWORD(lParam); ptEnd.y = HIWORD(lParam); if (flag == 0) p = new CLine(ptStart, ptEnd); else p = new CEllipse(ptStart, ptEnd); myGraph.push_back(p); InvalidateRect(hWnd, NULL, TRUE); break; case WM_CREATE: hMenu = LoadMenu(::GetModuleHandle(NULL), LPCTSTR(IDR_MENU)); SetMenu(hWnd, hMenu); break; case WM_COMMAND: switch(LOWORD(wParam)) { case ID_MENU_EXIT: PostQuitMessage(0); break; case ID_MENU_LINE: flag = 0; break; case ID_MENU_ELLIPSE: flag = 1; break; } break; case WM_PAINT: hdc=BeginPaint(hWnd,&ps); for (iter = myGraph.begin(); iter != myGraph.end(); iter++) { (*iter)->OnDraw(hdc); } EndPaint(hWnd,&ps); return 0; case WM_DESTROY: PostQuitMessage(0); return 0; } return DefWindowProc(hWnd,message,wParam,lParam); }