【发布时间】:2012-01-20 07:13:36
【问题描述】:
我们在没有域控制器的网络 (LAN) 设置中连接了几台打印机。打印机被赋予特定的 IP 地址。我希望将所有打印机活动记录到数据库(或文件系统)。我还想控制打印机,例如,如果任何用户(来自 IP 地址)希望横向打印,但我的打印机配置为仅纵向打印,则打印机应拒绝打印。另一个例子是如果用户超过了打印限制(页数),打印机不应该打印下一页。
我不知道要实现这一点。请提出您宝贵的建议。代码sn-ps,欢迎提出意见。
【问题讨论】:
我们在没有域控制器的网络 (LAN) 设置中连接了几台打印机。打印机被赋予特定的 IP 地址。我希望将所有打印机活动记录到数据库(或文件系统)。我还想控制打印机,例如,如果任何用户(来自 IP 地址)希望横向打印,但我的打印机配置为仅纵向打印,则打印机应拒绝打印。另一个例子是如果用户超过了打印限制(页数),打印机不应该打印下一页。
我不知道要实现这一点。请提出您宝贵的建议。代码sn-ps,欢迎提出意见。
【问题讨论】:
请查看 MSDN 上的 Print Spooler API 函数:http://msdn.microsoft.com/en-us/library/dd162861(v=VS.85).aspx
如何正确调用 Win32 后台处理程序枚举 API:http://support.microsoft.com/kb/158828
如何获取打印机和打印作业的状态:http://support.microsoft.com/kb/160129
示例代码:
BOOL GetJobs(HANDLE hPrinter, /* Handle to the printer. */
JOB_INFO_2 **ppJobInfo, /* Pointer to be filled. */
int *pcJobs, /* Count of jobs filled. */
DWORD *pStatus) /* Print Queue status. */
{
DWORD cByteNeeded,
nReturned,
cByteUsed;
JOB_INFO_2 *pJobStorage = NULL;
PRINTER_INFO_2 *pPrinterInfo = NULL;
/* Get the buffer size needed. */
if (!GetPrinter(hPrinter, 2, NULL, 0, &cByteNeeded))
{
if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
return FALSE;
}
pPrinterInfo = (PRINTER_INFO_2 *)malloc(cByteNeeded);
if (!(pPrinterInfo))
/* Failure to allocate memory. */
return FALSE;
/* Get the printer information. */
if (!GetPrinter(hPrinter,
2,
(LPSTR)pPrinterInfo,
cByteNeeded,
&cByteUsed))
{
/* Failure to access the printer. */
free(pPrinterInfo);
pPrinterInfo = NULL;
return FALSE;
}
/* Get job storage space. */
if (!EnumJobs(hPrinter,
0,
pPrinterInfo->cJobs,
2,
NULL,
0,
(LPDWORD)&cByteNeeded,
(LPDWORD)&nReturned))
{
if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
{
free(pPrinterInfo);
pPrinterInfo = NULL;
return FALSE;
}
}
pJobStorage = (JOB_INFO_2 *)malloc(cByteNeeded);
if (!pJobStorage)
{
/* Failure to allocate Job storage space. */
free(pPrinterInfo);
pPrinterInfo = NULL;
return FALSE;
}
ZeroMemory(pJobStorage, cByteNeeded);
/* Get the list of jobs. */
if (!EnumJobs(hPrinter,
0,
pPrinterInfo->cJobs,
2,
(LPBYTE)pJobStorage,
cByteNeeded,
(LPDWORD)&cByteUsed,
(LPDWORD)&nReturned))
{
free(pPrinterInfo);
free(pJobStorage);
pJobStorage = NULL;
pPrinterInfo = NULL;
return FALSE;
}
/*
* Return the information.
*/
*pcJobs = nReturned;
*pStatus = pPrinterInfo->Status;
*ppJobInfo = pJobStorage;
free(pPrinterInfo);
return TRUE;
}
BOOL IsPrinterError(HANDLE hPrinter)
{
JOB_INFO_2 *pJobs;
int cJobs,
i;
DWORD dwPrinterStatus;
/*
* Get the state information for the Printer Queue and
* the jobs in the Printer Queue.
*/
if (!GetJobs(hPrinter, &pJobs, &cJobs, &dwPrinterStatus))
return FALSE;
/*
* If the Printer reports an error, believe it.
*/
if (dwPrinterStatus &
(PRINTER_STATUS_ERROR |
PRINTER_STATUS_PAPER_JAM |
PRINTER_STATUS_PAPER_OUT |
PRINTER_STATUS_PAPER_PROBLEM |
PRINTER_STATUS_OUTPUT_BIN_FULL |
PRINTER_STATUS_NOT_AVAILABLE |
PRINTER_STATUS_NO_TONER |
PRINTER_STATUS_OUT_OF_MEMORY |
PRINTER_STATUS_OFFLINE |
PRINTER_STATUS_DOOR_OPEN))
{
free( pJobs );
return TRUE;
}
/*
* Find the Job in the Queue that is printing.
*/
for (i=0; i < cJobs; i++)
{
if (pJobs[i].Status & JOB_STATUS_PRINTING)
{
/*
* If the job is in an error state,
* report an error for the printer.
* Code could be inserted here to
* attempt an interpretation of the
* pStatus member as well.
*/
if (pJobs[i].Status &
(JOB_STATUS_ERROR |
JOB_STATUS_OFFLINE |
JOB_STATUS_PAPEROUT |
JOB_STATUS_BLOCKED_DEVQ))
{
free( pJobs );
return TRUE;
}
}
}
/*
* No error condition.
*/
free( pJobs );
return FALSE;
}
【讨论】: