问题
I am writing a C# program to change the orientation of print job. Here is how I am doing it
• Open Printer using OpenPrinter()
• Get the job details with JOB_INFO_2 structure using GetJob()
• Change the orientation in JOB_INFO_2 structure
• Set the JOB_INFO_2 structure using SetJob()
But when I call SetJob() method it always fails with the return code 122. I am opening printer with PRINTER_ALL_ACCESS. (I have also tried with PRINTER_ACCESS_ADMINISTER but no luck). The printer I am using is local printer.
What am I doing wrong?
Here is my code
public class PrintJob
{
#region Native Method Imports
[DllImport("winspool.drv", EntryPoint = "OpenPrinter", SetLastError = true, CharSet = CharSet.Unicode, ExactSpelling = false, CallingConvention = CallingConvention.StdCall)]
public static extern bool OpenPrinter(string pPrinterName, out IntPtr phPrinter, ref PRINTER_DEFAULTS pDefault);
[DllImport("winspool.drv", EntryPoint = "ClosePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
public static extern bool ClosePrinter(IntPtr hPrinter);
[DllImport("winspool.drv", EntryPoint = "GetJob", SetLastError = true, CharSet = CharSet.Auto, ExactSpelling = false, CallingConvention = CallingConvention.StdCall)]
public static extern bool GetJob(IntPtr hPrinter, Int32 dwJobId, Int32 Level, IntPtr lpJob, Int32 cbBuf, ref Int32 lpbSizeNeeded);
[DllImport("winspool.drv", EntryPoint = "GetJob", SetLastError = true, CharSet = CharSet.Auto, ExactSpelling = false, CallingConvention = CallingConvention.StdCall)]
public static extern bool GetJob(Int32 hPrinter, Int32 dwJobId, Int32 Level, IntPtr lpJob, Int32 cbBuf, ref Int32 lpbSizeNeeded);
[DllImport("winspool.drv", EntryPoint = "SetJobA")]
public static extern bool SetJob(IntPtr hPrinter, int JobId, int Level, IntPtr pJob, int Command_Renamed);
[StructLayout(LayoutKind.Sequential)]
internal struct PRINTER_DEFAULTS
{
public int pDatatype;
public int pDevMode;
public uint DesiredAccess;
}
private const int DM_ORIENTATION = 0x1;
#endregion
public void ChangePrintOrientation(string printerName, int jobId)
{
IntPtr _printerHandle = IntPtr.Zero;
PRINTER_DEFAULTS pDefaults = new PRINTER_DEFAULTS();
pDefaults.DesiredAccess = 0xf000c; // PRINTER_ALL_ACCESS;
pDefaults.pDatatype = 0;
pDefaults.pDevMode = 0;
//Open the printer
OpenPrinter(printerName, out _printerHandle, ref pDefaults);
if (_printerHandle == IntPtr.Zero)
{
throw new Exception("OpenPrinter() Failed with error code " + Marshal.GetLastWin32Error());
}
//Get the JOB details from GetJob()
JOB_INFO_2 jobInfo = GetJobInfo2(_printerHandle, jobId);
if(jobInfo == null)
{
throw new Exception("Could not get job details");
}
//Set the orientation
jobInfo.DeviceMode.dmFields = DM_ORIENTATION;
jobInfo.DeviceMode.dmOrientation = 2;//LANDSCAPE
IntPtr ptr = Marshal.AllocHGlobal(Marshal.SizeOf(jobInfo));
Marshal.StructureToPtr(jobInfo, ptr, false);
//Set the job
if(!SetJob(_printerHandle, jobId, 2, ptr, 0)) //Here i always get 122 from the function
{
throw new Exception("SetJob() Failed with error code " + Marshal.GetLastWin32Error());
}
//Finally close the printer
ClosePrinter(_printerHandle);
}
private JOB_INFO_2 GetJobInfo2(IntPtr _printerHandle, int jobId)
{
JOB_INFO_2 info = null;
Int32 BytesWritten = default(Int32);
IntPtr ptBuf = default(IntPtr);
//Get the required buffer size
if (!GetJob(_printerHandle, jobId, 2, ptBuf, 0, ref BytesWritten))
{
if (BytesWritten == 0)
{
throw new Exception("GetJob for JOB_INFO_2 failed on handle: " + _printerHandle.ToString() + " for job: " + jobId);
}
}
//Allocate a buffer the right size
if (BytesWritten > 0)
{
ptBuf = Marshal.AllocHGlobal(BytesWritten * 2);
}
if (!GetJob(_printerHandle, jobId, 2, ptBuf, BytesWritten, ref BytesWritten))
{
throw new Exception("GetJob for JOB_INFO_2 failed on handle: " + _printerHandle.ToString() + " for job: " + jobId);
}
else
{
info = new JOB_INFO_2();
Marshal.PtrToStructure(ptBuf, info);
//Fill the devmode structure
IntPtr ptrDevMode = new IntPtr(info.LPDeviceMode);
Marshal.PtrToStructure(ptrDevMode, info.dmOut);
}
//\\ Free the allocated memory
Marshal.FreeHGlobal(ptBuf);
return info;
}
}
I have taken DEVMODE structure from here.
回答1:
This code works. It deletes Print Job.
BOOL JobControlPause(wstring strPrinterName)
{
PRINTER_DEFAULTS pd;
ZeroMemory(&pd, sizeof(pd));
pd.DesiredAccess = PRINTER_ALL_ACCESS;
DWORD dwSize;
char szPrinterName[100];
BOOL bOK;
HANDLE hPrinter = NULL;
PRINTER_INFO_2 *pPrinterInfo = NULL;
DWORD dwReturned, dwNeeded, dwJobCount;
JOB_INFO_2 *pJobInfo;
dwSize = 100;
//// default printer
//GetProfileString("windows", "device", "", szPrinterName, dwSize);
//// Printer name precedes first "," character...
//strtok(szPrinterName, ",");
// get the printer handle
bOK = OpenPrinter((LPWSTR)strPrinterName.c_str(), &hPrinter, &pd);
if (!bOK)
return 1;
// get byte count needed for buffer
GetPrinter(hPrinter, 2, NULL, 0, &dwNeeded);
// alocate the buffer
pPrinterInfo = new PRINTER_INFO_2[dwNeeded +5];
// get an information about the printer
bOK = GetPrinter(hPrinter, 2, (LPBYTE)pPrinterInfo, dwNeeded, &dwReturned);
if (!bOK)
return FALSE;
// alocate the structure
EnumJobs(hPrinter, 0, pPrinterInfo->cJobs, 2, NULL, 0,
(LPDWORD)&dwNeeded, (LPDWORD)&dwReturned);
pJobInfo = new JOB_INFO_2[dwNeeded];
// enum the jobs
if (!EnumJobs(hPrinter, 0, pPrinterInfo->cJobs, 2, (LPBYTE)pJobInfo,
dwNeeded, &dwReturned, &dwJobCount))
{
return 1;
}
// pause all jobs
for (DWORD i=0; i<dwJobCount; i++)
{
bOK = SetJob(hPrinter, pJobInfo[i].JobId, 2, (LPBYTE)pJobInfo, JOB_CONTROL_DELETE);
if (!bOK)
{
//MessageBox(NULL, "Error", "Error", MB_OK);
return FALSE;
}
}
return TRUE;
}
回答2:
the return value is based the following rule: If the function succeeds, the return value is a nonzero value. If the function fails, the return value is zero.
while your code is : if(!SetJob(_printerHandle, jobId, 2, ptr, 0)) //Here i always get 122 from the function { throw new Exception("SetJob() Failed with error code " + Marshal.GetLastWin32Error()); }
it means when SetJob ruturn sucess, code throw exception
来源：https://stackoverflow.com/questions/8082445/setjob-method-always-returns-122