Hi Alex ,
Thanks for your feedback.
I have created a test Power Users account on my machine, then test your
sample code in this account. Yes, I can reproduce out this problem on my
side. This exception occurs in PrintPreviewDialog.CreateHandle.
If we use Reflector to view the source code, we will see that:
protected override void CreateHandle()
{
if ((this.Document != null) &&
!this.Document.PrinterSettings.IsValid)
{
throw new
InvalidPrinterException(this.Document.PrinterSettings);
}
base.CreateHandle();
}
Then I added the test code:
bool f=this.printDocument1.PrinterSettings.IsValid;
For the test account, the result is false, which caused out the
InvalidPrinterException exception.
Further invest in System.Drawing.Printing.PrinterSettings.IsValid in
Reflector, I got the following code:
public bool IsValid
{
get
{
return (this.DeviceCapabilities(0x12, IntPtr.Zero, -1) != -1);
}
}
private int DeviceCapabilities(short capability, IntPtr pointerToBuffer,
int defaultValue)
{
IntSecurity.AllPrinting.Assert();
string text1 = this.PrinterName;
CodeAccessPermission.RevertAssert();
IntSecurity.UnmanagedCode.Assert();
return this.FastDeviceCapabilities(capability, pointerToBuffer,
defaultValue, text1);
}
private int FastDeviceCapabilities(short capability, IntPtr
pointerToBuffer, int defaultValue, string printerName)
{
int num1 = SafeNativeMethods.DeviceCapabilities(printerName,
this.OutputPort, capability, pointerToBuffer, IntPtr.Zero);
if (num1 == -1)
{
return defaultValue;
}
return num1;
}
After setting breakpoing in these methods one-by-one(you should setup the
debug symbols correctly, also, I used Win2003 RunAs function to run VS.net
under the test accout, so that I can do debugging under this test
account),
I find that DeviceCapabilities Win32 API failed and returns -1. Calling
System.Runtime.InteropServices.Marshal.GetLastWin32Error(), I got the
error
message below: "The printer name is invalid".
It seems that PrinterSettings.PrinterName property returns the incorrect
printer name. Then I checked into the PrinterName property, I get these:
public string get_PrinterName()
{
IntSecurity.AllPrinting.Demand();
return this.PrinterNameInternal;
}
private string get_PrinterNameInternal()
{
if (this.printerName == null)
{
return PrinterSettings.GetDefaultPrinterName();
}
return this.printerName;
}
private static string GetDefaultPrinterName()
{
IntSecurity.UnmanagedCode.Assert();
SafeNativeMethods.PRINTDLG printdlg1 =
PrinterSettings.CreatePRINTDLG();
printdlg1.Flags = 0x400;
if (!SafeNativeMethods.PrintDlg(printdlg1))
{
return SR.GetString("NoDefaultPrinter");
}
IntPtr ptr1 = printdlg1.hDevNames;
IntPtr ptr2 = SafeNativeMethods.GlobalLock(new HandleRef(printdlg1,
ptr1));
if (ptr2 == IntPtr.Zero)
{
throw new Win32Exception();
}
string text1 = PrinterSettings.ReadOneDEVNAME(ptr2, 1);
SafeNativeMethods.GlobalUnlock(new HandleRef(printdlg1, ptr1));
ptr2 = IntPtr.Zero;
SafeNativeMethods.GlobalFree(new HandleRef(printdlg1,
printdlg1.hDevNames));
SafeNativeMethods.GlobalFree(new HandleRef(printdlg1,
printdlg1.hDevMode));
return text1;
}
I finally get that the SafeNativeMethods.PrintDlg return false, so no
default printer name is returned(returned by
SR.GetString("NoDefaultPrinter"); statement).
SafeNativeMethods.PrintDlg is a Win32 API, which .Net p/invoked it. Then I
write a MFC application to test this API in Win32 world:
void CMFCPrintDlgTestDlg::OnBnClickedButton1()
{
PRINTDLG printdlg1;
HWND hwnd;
// Initialize PRINTDLG
ZeroMemory(&printdlg1, sizeof(printdlg1));
printdlg1.lStructSize = 0x42;
printdlg1.hwndOwner = 0;
printdlg1.hDevMode = 0;
printdlg1.hDevNames = 0;
printdlg1.Flags = 0;
printdlg1.hwndOwner = 0;
printdlg1.hDC = 0;
printdlg1.nFromPage = 1;
printdlg1.nToPage = 1;
printdlg1.nMinPage = 0;
printdlg1.nMaxPage = 0x270f;
printdlg1.nCopies = 1;
printdlg1.hInstance = 0;
printdlg1.lCustData = 0;
printdlg1.lpfnPrintHook = NULL;
printdlg1.lpfnSetupHook = NULL;
printdlg1.lpPrintTemplateName = NULL;
printdlg1.lpSetupTemplateName = NULL;
printdlg1.hPrintTemplate = 0;
printdlg1.hSetupTemplate = 0;
printdlg1.Flags = 0x400;
if (PrintDlg(&printdlg1)==TRUE)
{
MessageBox("Succeeded!");
DeleteDC(printdlg1.hDC);
}
else
{
char buf[50];
wsprintf(buf, "error: %d",GetLastError());
MessageBox(buf, buf);
}
}
Testing with the test account, I also can reproduce out the problem. Also,
the key point is for setting PRINTDLG.Flags to 0x400, which is
PD_RETURNDEFAULT const.
Yes, after enabling "Manage Documents" permission on the printer for test
account, the problem will go away. But I am not sure why PrintDlg with
PD_RETURNDEFAULT require "Manage Documents" permission.
Currently, I do not think there is any good solution for this issue, maybe
we have to setup "Manage Documents" permission for all the non-admin
accounts.(Yes, you can documented this in your application)
Finally, if you want to submit a bug for microsoft, I suggest you contact
Microsoft PSS for it.
You can contact Microsoft Product Support by contacting us at
1-(800)936-5800 or by choosing one of the options listed at
http://www.microsoft.com/services/microsoftservices/supp.mspx
Hope this information helps
Best regards,
Jeffrey Tan
Microsoft Online Partner Support
Get Secure! -
www.microsoft.com/security
This posting is provided "as is" with no warranties and confers no rights.
