我正在寻找一种方法来使用非托管 C++ 查找 Windows 默认打印机的名称（找到大量 .NET 示例，但没有成功非托管）。谢谢。
Blumer
问问题
7977 次
5 回答
3
以下内容非常适合使用 C++ 中的 win32api 进行打印
char szPrinterName[255];
unsigned long lPrinterNameLength;
GetDefaultPrinter( szPrinterName, &lPrinterNameLength );
HDC hPrinterDC;
hPrinterDC = CreateDC("WINSPOOL\0", szPrinterName, NULL, NULL);
将来不要使用谷歌搜索“非托管”，而是尝试谷歌搜索“win32 /subject/”或“win32 api /subject/”
于 2008-09-19T19:39:36.953 回答
3
以下是如何获取当前打印机列表和默认打印机列表（如果有一台设置为默认打印机）。
另请注意：如果用户没有打印机或未将默认设置为 1，则默认打印机名称长度为零是有效的。
还应该支持处理长打印机名称，因此首先使用 NULL 作为缓冲区指针调用 GetDefaultPrinter 将返回名称长度，然后您可以分配一个足够大的名称缓冲区来保存名称。
DWORD numprinters;
DWORD defprinter=0;
DWORD dwSizeNeeded=0;
DWORD dwItem;
LPPRINTER_INFO_2 printerinfo = NULL;
// Get buffer size
EnumPrinters ( PRINTER_ENUM_LOCAL | PRINTER_ENUM_CONNECTIONS , NULL, 2, NULL, 0, &dwSizeNeeded, &numprinters );
// allocate memory
//printerinfo = (LPPRINTER_INFO_2)HeapAlloc ( GetProcessHeap (), HEAP_ZERO_MEMORY, dwSizeNeeded );
printerinfo = (LPPRINTER_INFO_2)new char[dwSizeNeeded];
if ( EnumPrinters ( PRINTER_ENUM_LOCAL | PRINTER_ENUM_CONNECTIONS, // what to enumerate
NULL, // printer name (NULL for all)
2, // level
(LPBYTE)printerinfo, // buffer
dwSizeNeeded, // size of buffer
&dwSizeNeeded, // returns size
&numprinters // return num. items
) == 0 )
{
numprinters=0;
}
{
DWORD size=0;
// Get the size of the default printer name.
GetDefaultPrinter(NULL, &size);
if(size)
{
// Allocate a buffer large enough to hold the printer name.
TCHAR* buffer = new TCHAR[size];
// Get the printer name.
GetDefaultPrinter(buffer, &size);
for ( dwItem = 0; dwItem < numprinters; dwItem++ )
{
if(!strcmp(buffer,printerinfo[dwItem].pPrinterName))
defprinter=dwItem;
}
delete buffer;
}
}
于 2008-09-19T19:42:35.293 回答
2
如何在 Windows 中检索和设置默认打印机：
http://support.microsoft.com/default.aspx?scid=kb;EN-US;246772
来自现在不可用文章的代码：
// You are explicitly linking to GetDefaultPrinter because linking
// implicitly on Windows 95/98 or NT4 results in a runtime error.
// This block specifies which text version you explicitly link to.
#ifdef UNICODE
#define GETDEFAULTPRINTER "GetDefaultPrinterW"
#else
#define GETDEFAULTPRINTER "GetDefaultPrinterA"
#endif
// Size of internal buffer used to hold "printername,drivername,portname"
// string. You may have to increase this for huge strings.
#define MAXBUFFERSIZE 250
/*----------------------------------------------------------------*/
/* DPGetDefaultPrinter */
/* */
/* Parameters: */
/* pPrinterName: Buffer alloc'd by caller to hold printer name. */
/* pdwBufferSize: On input, ptr to size of pPrinterName. */
/* On output, min required size of pPrinterName. */
/* */
/* NOTE: You must include enough space for the NULL terminator! */
/* */
/* Returns: TRUE for success, FALSE for failure. */
/*----------------------------------------------------------------*/
BOOL DPGetDefaultPrinter(LPTSTR pPrinterName, LPDWORD pdwBufferSize)
{
BOOL bFlag;
OSVERSIONINFO osv;
TCHAR cBuffer[MAXBUFFERSIZE];
PRINTER_INFO_2 *ppi2 = NULL;
DWORD dwNeeded = 0;
DWORD dwReturned = 0;
HMODULE hWinSpool = NULL;
PROC fnGetDefaultPrinter = NULL;
// What version of Windows are you running?
osv.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
GetVersionEx(&osv);
// If Windows 95 or 98, use EnumPrinters.
if (osv.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS)
{
// The first EnumPrinters() tells you how big our buffer must
// be to hold ALL of PRINTER_INFO_2. Note that this will
// typically return FALSE. This only means that the buffer (the 4th
// parameter) was not filled in. You do not want it filled in here.
SetLastError(0);
bFlag = EnumPrinters(PRINTER_ENUM_DEFAULT, NULL, 2, NULL, 0, &dwNeeded, &dwReturned);
{
if ((GetLastError() != ERROR_INSUFFICIENT_BUFFER) || (dwNeeded == 0))
return FALSE;
}
// Allocate enough space for PRINTER_INFO_2.
ppi2 = (PRINTER_INFO_2 *)GlobalAlloc(GPTR, dwNeeded);
if (!ppi2)
return FALSE;
// The second EnumPrinters() will fill in all the current information.
bFlag = EnumPrinters(PRINTER_ENUM_DEFAULT, NULL, 2, (LPBYTE)ppi2, dwNeeded, &dwNeeded, &dwReturned);
if (!bFlag)
{
GlobalFree(ppi2);
return FALSE;
}
// If specified buffer is too small, set required size and fail.
if ((DWORD)lstrlen(ppi2->pPrinterName) >= *pdwBufferSize)
{
*pdwBufferSize = (DWORD)lstrlen(ppi2->pPrinterName) + 1;
GlobalFree(ppi2);
return FALSE;
}
// Copy printer name into passed-in buffer.
lstrcpy(pPrinterName, ppi2->pPrinterName);
// Set buffer size parameter to minimum required buffer size.
*pdwBufferSize = (DWORD)lstrlen(ppi2->pPrinterName) + 1;
}
// If Windows NT, use the GetDefaultPrinter API for Windows 2000,
// or GetProfileString for version 4.0 and earlier.
else if (osv.dwPlatformId == VER_PLATFORM_WIN32_NT)
{
if (osv.dwMajorVersion >= 5) // Windows 2000 or later (use explicit call)
{
hWinSpool = LoadLibrary("winspool.drv");
if (!hWinSpool)
return FALSE;
fnGetDefaultPrinter = GetProcAddress(hWinSpool, GETDEFAULTPRINTER);
if (!fnGetDefaultPrinter)
{
FreeLibrary(hWinSpool);
return FALSE;
}
bFlag = fnGetDefaultPrinter(pPrinterName, pdwBufferSize);
FreeLibrary(hWinSpool);
if (!bFlag)
return FALSE;
}
else // NT4.0 or earlier
{
// Retrieve the default string from Win.ini (the registry).
// String will be in form "printername,drivername,portname".
if (GetProfileString("windows", "device", ",,,", cBuffer, MAXBUFFERSIZE) <= 0)
return FALSE;
// Printer name precedes first "," character.
strtok(cBuffer, ",");
// If specified buffer is too small, set required size and fail.
if ((DWORD)lstrlen(cBuffer) >= *pdwBufferSize)
{
*pdwBufferSize = (DWORD)lstrlen(cBuffer) + 1;
return FALSE;
}
// Copy printer name into passed-in buffer.
lstrcpy(pPrinterName, cBuffer);
// Set buffer size parameter to minimum required buffer size.
*pdwBufferSize = (DWORD)lstrlen(cBuffer) + 1;
}
}
// Clean up.
if (ppi2)
GlobalFree(ppi2);
return TRUE;
}
#undef MAXBUFFERSIZE
#undef GETDEFAULTPRINTER
// You are explicitly linking to SetDefaultPrinter because implicitly
// linking on Windows 95/98 or NT4 results in a runtime error.
// This block specifies which text version you explicitly link to.
#ifdef UNICODE
#define SETDEFAULTPRINTER "SetDefaultPrinterW"
#else
#define SETDEFAULTPRINTER "SetDefaultPrinterA"
#endif
/*-----------------------------------------------------------------*/
/* DPSetDefaultPrinter */
/* */
/* Parameters: */
/* pPrinterName: Valid name of existing printer to make default. */
/* */
/* Returns: TRUE for success, FALSE for failure. */
/*-----------------------------------------------------------------*/
BOOL DPSetDefaultPrinter(LPTSTR pPrinterName)
{
BOOL bFlag;
OSVERSIONINFO osv;
DWORD dwNeeded = 0;
HANDLE hPrinter = NULL;
PRINTER_INFO_2 *ppi2 = NULL;
LPTSTR pBuffer = NULL;
LONG lResult;
HMODULE hWinSpool = NULL;
PROC fnSetDefaultPrinter = NULL;
// What version of Windows are you running?
osv.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
GetVersionEx(&osv);
if (!pPrinterName)
return FALSE;
// If Windows 95 or 98, use SetPrinter.
if (osv.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS)
{
// Open this printer so you can get information about it.
bFlag = OpenPrinter(pPrinterName, &hPrinter, NULL);
if (!bFlag || !hPrinter)
return FALSE;
// The first GetPrinter() tells you how big our buffer must
// be to hold ALL of PRINTER_INFO_2. Note that this will
// typically return FALSE. This only means that the buffer (the 3rd
// parameter) was not filled in. You do not want it filled in here.
SetLastError(0);
bFlag = GetPrinter(hPrinter, 2, 0, 0, &dwNeeded);
if (!bFlag)
{
if ((GetLastError() != ERROR_INSUFFICIENT_BUFFER) || (dwNeeded == 0))
{
ClosePrinter(hPrinter);
return FALSE;
}
}
// Allocate enough space for PRINTER_INFO_2.
ppi2 = (PRINTER_INFO_2 *)GlobalAlloc(GPTR, dwNeeded);
if (!ppi2)
{
ClosePrinter(hPrinter);
return FALSE;
}
// The second GetPrinter() will fill in all the current information
// so that all you have to do is modify what you are interested in.
bFlag = GetPrinter(hPrinter, 2, (LPBYTE)ppi2, dwNeeded, &dwNeeded);
if (!bFlag)
{
ClosePrinter(hPrinter);
GlobalFree(ppi2);
return FALSE;
}
// Set default printer attribute for this printer.
ppi2->Attributes |= PRINTER_ATTRIBUTE_DEFAULT;
bFlag = SetPrinter(hPrinter, 2, (LPBYTE)ppi2, 0);
if (!bFlag)
{
ClosePrinter(hPrinter);
GlobalFree(ppi2);
return FALSE;
}
// Tell all open programs that this change occurred.
// Allow each program 1 second to handle this message.
lResult = SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE, 0L,
(LPARAM)(LPCTSTR)"windows", SMTO_NORMAL, 1000, NULL);
}
// If Windows NT, use the SetDefaultPrinter API for Windows 2000,
// or WriteProfileString for version 4.0 and earlier.
else if (osv.dwPlatformId == VER_PLATFORM_WIN32_NT)
{
if (osv.dwMajorVersion >= 5) // Windows 2000 or later (use explicit call)
{
hWinSpool = LoadLibrary("winspool.drv");
if (!hWinSpool)
return FALSE;
fnSetDefaultPrinter = GetProcAddress(hWinSpool, SETDEFAULTPRINTER);
if (!fnSetDefaultPrinter)
{
FreeLibrary(hWinSpool);
return FALSE;
}
bFlag = fnSetDefaultPrinter(pPrinterName);
FreeLibrary(hWinSpool);
if (!bFlag)
return FALSE;
}
else // NT4.0 or earlier
{
// Open this printer so you can get information about it.
bFlag = OpenPrinter(pPrinterName, &hPrinter, NULL);
if (!bFlag || !hPrinter)
return FALSE;
// The first GetPrinter() tells you how big our buffer must
// be to hold ALL of PRINTER_INFO_2. Note that this will
// typically return FALSE. This only means that the buffer (the 3rd
// parameter) was not filled in. You do not want it filled in here.
SetLastError(0);
bFlag = GetPrinter(hPrinter, 2, 0, 0, &dwNeeded);
if (!bFlag)
{
if ((GetLastError() != ERROR_INSUFFICIENT_BUFFER) || (dwNeeded == 0))
{
ClosePrinter(hPrinter);
return FALSE;
}
}
// Allocate enough space for PRINTER_INFO_2.
ppi2 = (PRINTER_INFO_2 *)GlobalAlloc(GPTR, dwNeeded);
if (!ppi2)
{
ClosePrinter(hPrinter);
return FALSE;
}
// The second GetPrinter() fills in all the current<BR/>
// information.
bFlag = GetPrinter(hPrinter, 2, (LPBYTE)ppi2, dwNeeded, &dwNeeded);
if ((!bFlag) || (!ppi2->pDriverName) || (!ppi2->pPortName))
{
ClosePrinter(hPrinter);
GlobalFree(ppi2);
return FALSE;
}
// Allocate buffer big enough for concatenated string.
// String will be in form "printername,drivername,portname".
pBuffer = (LPTSTR)GlobalAlloc(GPTR,
lstrlen(pPrinterName) +
lstrlen(ppi2->pDriverName) +
lstrlen(ppi2->pPortName) + 3);
if (!pBuffer)
{
ClosePrinter(hPrinter);
GlobalFree(ppi2);
return FALSE;
}
// Build string in form "printername,drivername,portname".
lstrcpy(pBuffer, pPrinterName); lstrcat(pBuffer, ",");
lstrcat(pBuffer, ppi2->pDriverName); lstrcat(pBuffer, ",");
lstrcat(pBuffer, ppi2->pPortName);
// Set the default printer in Win.ini and registry.
bFlag = WriteProfileString("windows", "device", pBuffer);
if (!bFlag)
{
ClosePrinter(hPrinter);
GlobalFree(ppi2);
GlobalFree(pBuffer);
return FALSE;
}
}
// Tell all open programs that this change occurred.
// Allow each app 1 second to handle this message.
lResult = SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE, 0L, 0L,
SMTO_NORMAL, 1000, NULL);
}
// Clean up.
if (hPrinter)
ClosePrinter(hPrinter);
if (ppi2)
GlobalFree(ppi2);
if (pBuffer)
GlobalFree(pBuffer);
return TRUE;
}
#undef SETDEFAULTPRINTER
于 2008-09-19T19:46:03.553 回答
1
GetDefaultPrinter (MSDN)应该可以解决问题。这将使您获得传递给 CreateDC 以进行打印的名称。
于 2008-09-19T19:41:59.723 回答
-1
非托管 C++ 不存在（托管 C++ 现在是 C++/CLI），如果您指的是 C++，则使用非托管作为标记只是可悲...
于 2008-09-19T19:43:50.453 回答