SYSMETS4.docx

1、SYSMETS4/*- SYSMETS4.C - System Metrics Display Program No. 4 (c) Charles Petzold, 1998 -*/#define WINVER 0x0500#include #include sysmets.hLRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) static TCH

2、AR szAppName = TEXT (SysMets4) ; 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.hCu

3、rsor = LoadCursor (NULL, IDC_ARROW) ; wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ; wndclass.lpszMenuName = NULL ; wndclass.lpszClassName = szAppName ; if (!RegisterClass (&wndclass) MessageBox (NULL, TEXT (Program requires Windows NT!), szAppName, MB_ICONERROR) ; return 0 ; hwnd

4、= CreateWindow (szAppName, TEXT (Get System Metrics No. 4), WS_OVERLAPPEDWINDOW | WS_VSCROLL | WS_HSCROLL, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL) ; ShowWindow (hwnd, iCmdShow) ; UpdateWindow (hwnd) ; while (GetMessage (&msg, NULL, 0, 0) TranslateMess

5、age (&msg) ; DispatchMessage (&msg) ; return msg.wParam ;LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) static int cxChar, cxCaps, cyChar, cxClient, cyClient, iMaxWidth ; HDC hdc ; int i, x, y, iVertPos, iHorzPos, iPaintBeg, iPaintEnd ; PAINTSTRUCT ps ; SCROLLINFO s

6、i ; TCHAR szBuffer10 ; TEXTMETRIC tm ; switch (message) case WM_CREATE: hdc = GetDC (hwnd) ; GetTextMetrics (hdc, &tm) ; cxChar = tm.tmAveCharWidth ; cxCaps = (tm.tmPitchAndFamily & 1 ? 3 : 2) * cxChar / 2 ; cyChar = tm.tmHeight + tm.tmExternalLeading ; ReleaseDC (hwnd, hdc) ; / Save the width of th

7、e three columns iMaxWidth = 40 * cxChar + 22 * cxCaps ; return 0 ; case WM_SIZE: cxClient = LOWORD (lParam) ; cyClient = HIWORD (lParam) ; / Set vertical scroll bar range and page size si.cbSize = sizeof (si) ; si.fMask = SIF_RANGE | SIF_PAGE ; si.nMin = 0 ; si.nMax = NUMLINES - 1 ; si.nPage = cyCli

8、ent / cyChar ; SetScrollInfo (hwnd, SB_VERT, &si, TRUE) ; / Set horizontal scroll bar range and page size si.cbSize = sizeof (si) ; si.fMask = SIF_RANGE | SIF_PAGE ; si.nMin = 0 ; si.nMax = 2 + iMaxWidth / cxChar ; si.nPage = cxClient / cxChar ; SetScrollInfo (hwnd, SB_HORZ, &si, TRUE) ; return 0 ;

9、case WM_VSCROLL: / Get all the vertical scroll bar information si.cbSize = sizeof (si) ; si.fMask = SIF_ALL ; GetScrollInfo (hwnd, SB_VERT, &si) ; / Save the position for comparison later on iVertPos = si.nPos ; switch (LOWORD (wParam) case SB_TOP: si.nPos = si.nMin ; break ; case SB_BOTTOM: si.nPos

10、 = si.nMax ; break ; case SB_LINEUP: si.nPos -= 1 ; break ; case SB_LINEDOWN: si.nPos += 1 ; break ; case SB_PAGEUP: si.nPos -= si.nPage ; break ; case SB_PAGEDOWN: si.nPos += si.nPage ; break ; case SB_THUMBTRACK: si.nPos = si.nTrackPos ; break ; default: break ; / Set the position and then retriev

11、e it. Due to adjustments / by Windows it might not be the same as the value set. si.fMask = SIF_POS ; SetScrollInfo (hwnd, SB_VERT, &si, TRUE) ; GetScrollInfo (hwnd, SB_VERT, &si) ; / If the position has changed, scroll the window and update it if (si.nPos != iVertPos) ScrollWindow (hwnd, 0, cyChar

12、* (iVertPos - si.nPos), NULL, NULL) ; UpdateWindow (hwnd) ; return 0 ; case WM_HSCROLL: / Get all the vertical scroll bar information si.cbSize = sizeof (si) ; si.fMask = SIF_ALL ; / Save the position for comparison later on GetScrollInfo (hwnd, SB_HORZ, &si) ; iHorzPos = si.nPos ; switch (LOWORD (w

13、Param) case SB_LINELEFT: si.nPos -= 1 ; break ; case SB_LINERIGHT: si.nPos += 1 ; break ; case SB_PAGELEFT: si.nPos -= si.nPage ; break ; case SB_PAGERIGHT: si.nPos += si.nPage ; break ; case SB_THUMBPOSITION: si.nPos = si.nTrackPos ; break ; default: break ; / Set the position and then retrieve it.

14、 Due to adjustments / by Windows it might not be the same as the value set. si.fMask = SIF_POS ; SetScrollInfo (hwnd, SB_HORZ, &si, TRUE) ; GetScrollInfo (hwnd, SB_HORZ, &si) ; / If the position has changed, scroll the window if (si.nPos != iHorzPos) ScrollWindow (hwnd, cxChar * (iHorzPos - si.nPos)

15、, 0, NULL, NULL) ; return 0 ; case WM_KEYDOWN: switch (wParam) case VK_HOME: SendMessage (hwnd, WM_VSCROLL, SB_TOP, 0) ; break ; case VK_END: SendMessage (hwnd, WM_VSCROLL, SB_BOTTOM, 0) ; break ; case VK_PRIOR: SendMessage (hwnd, WM_VSCROLL, SB_PAGEUP, 0) ; break ; case VK_NEXT: SendMessage (hwnd,

16、WM_VSCROLL, SB_PAGEDOWN, 0) ; break ; case VK_UP: SendMessage (hwnd, WM_VSCROLL, SB_LINEUP, 0) ; break ; case VK_DOWN: SendMessage (hwnd, WM_VSCROLL, SB_LINEDOWN, 0) ; break ; case VK_LEFT: SendMessage (hwnd, WM_HSCROLL, SB_PAGEUP, 0) ; break ; case VK_RIGHT: SendMessage (hwnd, WM_HSCROLL, SB_PAGEDO

17、WN, 0) ; break ; return 0 ; case WM_PAINT: hdc = BeginPaint (hwnd, &ps) ; / Get vertical scroll bar position si.cbSize = sizeof (si) ; si.fMask = SIF_POS ; GetScrollInfo (hwnd, SB_VERT, &si) ; iVertPos = si.nPos ; / Get horizontal scroll bar position GetScrollInfo (hwnd, SB_HORZ, &si) ; iHorzPos = s

18、i.nPos ; / Find painting limits iPaintBeg = max (0, iVertPos + ps.rcPaint.top / cyChar) ; iPaintEnd = min (NUMLINES - 1, iVertPos + ps.rcPaint.bottom / cyChar) ; for (i = iPaintBeg ; i = iPaintEnd ; i+) x = cxChar * (1 - iHorzPos) ; y = cyChar * (i - iVertPos) ; TextOut (hdc, x, y, sysmetricsi.szLab

19、el, lstrlen (sysmetricsi.szLabel) ; TextOut (hdc, x + 22 * cxCaps, y, sysmetricsi.szDesc, lstrlen (sysmetricsi.szDesc) ; SetTextAlign (hdc, TA_RIGHT | TA_TOP) ; TextOut (hdc, x + 22 * cxCaps + 40 * cxChar, y, szBuffer, wsprintf (szBuffer, TEXT (%5d), GetSystemMetrics (sysmetricsi.iIndex) ; SetTextAlign (hdc, TA_LEFT | TA_TOP) ; EndPaint (hwnd, &ps) ; return 0 ; case WM_DESTROY: PostQuitMessage (0) ; return 0 ; return DefWindowProc (hwnd, message, wParam, lParam) ;