windows程序设计(DevCaps1代码)

//DEVCAPS1.C--Device Capabilities Display Program No.1 (c) Charles Petzold, 1998

#include <windows.h>

#define NUMLINES ((int) (sizeof(devcaps) / sizeof(devcaps[0])))
struct
{
int iIndex;
TCHAR *szLabel;
TCHAR *szDesc;
}
devcaps[] =
{
HORZSIZE, TEXT("HORZSIZE"), TEXT("Width in millimeters:"),
VERTSIZE, TEXT("VERTSIZE"), TEXT("Height in milimeters:"),
HORZRES, TEXT("HORZRES"), TEXT("Width in pixels:"),
VERTRES, TEXT("VERTRES"), TEXT("Height in raster lines:"),
BITSPIXEL, TEXT("BITSPIXEL"), TEXT("Color bits per pixel:"),
PLANES, TEXT("PLANES"), TEXT("Number of color planes:"),
NUMBRUSHES, TEXT("NUMBRUSHES"), TEXT("Number of device brushes"),
NUMPENS, TEXT("NUMPENS"), TEXT("Number of device pens:"),
NUMMARKERS, TEXT("NUMMARKERS"), TEXT("Number of device markers:"),
NUMFONTS, TEXT("NUMFONTS"), TEXT("Number of device fonts:"),
NUMCOLORS, TEXT("NUMCOLORS"), TEXT("Number of device colors:"),
PDEVICESIZE, TEXT("PDEVICESIZE"), TEXT("Size of device structure:"),
ASPECTX, TEXT("ASPECTX"), TEXT("Relative width of pixel:"),
ASPECTY, TEXT("ASPECTY"), TEXT("Relative height of pixel:"),
ASPECTXY, TEXT("ASPECTXY"), TEXT("Relative diagonal of pixel:"),
LOGPIXELSX, TEXT("LOGPIXELSX"), TEXT("Horizontal dots per inch:"),
LOGPIXELSY, TEXT("LOGPIXELSY"), TEXT("Vertical dots per inch:"),
SIZEPALETTE, TEXT("SIZEPALETTE"), TEXT("Number of palette entries:"),
NUMRESERVED, TEXT("NUMRESERVED"), TEXT("Reserved palette entries:"),
COLORRES, TEXT("COLORRES"), TEXT("Actual color resolution:")
};

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

int WINAPI WinMain( HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR lpCmdLine,int nShowCmd )
{
static TCHAR szAppName[] = TEXT("DevCaps1");
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 = szAppName;

if (!RegisterClass(&wndclass))
{
MessageBox(NULL, TEXT("This program requires Window NT!")
, szAppName, MB_ICONERROR);
return 0;
}

hwnd = CreateWindow(szAppName, TEXT("Device Capabilities")
, WS_OVERLAPPEDWINDOW
, CW_USEDEFAULT, CW_USEDEFAULT
, CW_USEDEFAULT, CW_USEDEFAULT
, NULL, NULL, hInstance, NULL);

ShowWindow(hwnd, nShowCmd);
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)
{
static int cxChar, cxCaps, cyChar;
TCHAR szBuffer[10];
HDC hdc;
int i;
PAINTSTRUCT ps;
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);
return 0;

case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
for (i = 0; i != NUMLINES; ++i)
{
TextOut(hdc, 0, cyChar * i, devcaps[i].szLabel
, lstrlen(devcaps[i].szLabel));
TextOut(hdc, 14 * cxCaps, cyChar * i, devcaps[i].szDesc
, lstrlen(devcaps[i].szDesc));
SetTextAlign(hdc, TA_RIGHT | TA_TOP);
TextOut(hdc, 14 * cxCaps + 35 * cxChar, cyChar * i, szBuffer
, wsprintf(szBuffer, TEXT("%5d"), GetDeviceCaps(hdc, devcaps[i].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);
}

 

 

//这个 TEXTOUT绘图 的代码  全部都是写在  WM_PAIN 消息内，意味着每次触发 该消息时  都会重新绘制。