Based on the suggestion in the comments here, I refactored my method to try to assign data to a MemoryStream outside of the iTextSharp.text.Document "using" (but within the MemoryStream using clause):
internal static HttpResponseMessage GeneratePDFOfReportFutures()
{
HttpResponseMessage result = null;
futureReports = GetAllFutureReports();
try
{
using (var ms = new MemoryStream())
{
using (var doc = new Document(PageSize.A4.Rotate(), 25, 25, 25, 25)) // the "Rotate" makes it landscape orientation
{
using (PdfWriter.GetInstance(doc, ms))
{
doc.Open();
. . .
// "int i" is for testing a quick exit of this long-running loop
int i = 0;
foreach (QueuedReports qr in futureReports)
{
var tblRow = new PdfPTable(6)
{
WidthPercentage = 80,
SpacingBefore = 4f
};
float[] tblRowWidths = new float[] { 220f, 180f, 220f, 160f, 160f, 340f };
tblRow.SetWidths(tblRowWidths);
tblRow.HorizontalAlignment = Element.ALIGN_LEFT;
var phraseRptName = new Phrase(qr.ReportName, helvetica9);
var cellRptName = GetCellForBorderedTable(phraseRptName, Element.ALIGN_CENTER, BaseColor.WHITE);
cellRptName.VerticalAlignment = Element.ALIGN_MIDDLE;
tblRow.AddCell(cellRptName);
. . .
tblRow.AddCell(cellRecipients);
doc.Add(tblRow);
i++;
if (i >= 12)
{
break;
}
} // foreach
} // pdfWriter
} // doc
var bytes = ms.ToArray();
result = new HttpResponseMessage(HttpStatusCode.OK)
{
Content = new ByteArrayContent(bytes)
};
result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = string.Format("{0}.pdf", "test")
};
result.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
} // memoryStream
} // try
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
return result;
} // GeneratePDFOfReportFutures
With a breakpoint in the "break" line, I step (F10) and the following exception is caught prior to reaching the assignment to bytes:
System.ObjectDisposedException was caught HResult=-2146232798
Message=Cannot access a closed Stream. Source=mscorlib
ObjectName="" StackTrace: at System.IO.__Error.StreamIsClosed() at System.IO.MemoryStream.Write(Byte[] buffer, Int32 offset, Int32 count) at iTextSharp.text.pdf.OutputStreamCounter.Write(Byte[] buffer, Int32 offset, Int32 count) at iTextSharp.text.pdf.PdfIndirectObject.WriteTo(Stream os) at iTextSharp.text.pdf.PdfWriter.PdfBody.Write(PdfIndirectObject indirect, Int32 refNumber, Int32 generation) at iTextSharp.text.pdf.PdfWriter.PdfBody.Add(PdfObject objecta, Int32 refNumber, Int32 generation, Boolean inObjStm) at iTextSharp.text.pdf.PdfWriter.PdfBody.Add(PdfObject objecta, PdfIndirectReference refa, Boolean inObjStm) at iTextSharp.text.pdf.PdfWriter.PdfBody.Add(PdfObject objecta, PdfIndirectReference refa) at iTextSharp.text.pdf.PdfWriter.AddToBody(PdfObject objecta, PdfIndirectReference refa) at iTextSharp.text.pdf.Type1Font.WriteFont(PdfWriter writer, PdfIndirectReference piref, Object[] parms) at iTextSharp.text.pdf.FontDetails.WriteFont(PdfWriter writer) at iTextSharp.text.pdf.PdfWriter.AddSharedObjectsToBody() at iTextSharp.text.pdf.PdfWriter.Close() at iTextSharp.text.DocWriter.Dispose()
Since accessing of PdfWriter and/or Doc appeared to be causing the problem, it would seem I need to move the writing code inside not only the doc using, but also the pdfWriter using, so I did that, moving the code like so:
. . .
} // foreach
var bytes = ms.ToArray();
result = new HttpResponseMessage(HttpStatusCode.OK)
{
Content = new ByteArrayContent(bytes)
};
result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = string.Format("{0}.pdf", "test")
};
result.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
} // pdfWriter
} // doc
} // memoryStream
} // try
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
return result;
...but I still get precisely the same exception. However, there is a difference between what I'm seeing now and what's described in the last post in that the exception is not thrown until I F10 on this line:
} // pdfWriter
If I move the return line above (and still keep it below the catch block) like so:
return result;
} // pdfWriter
...the exception is thrown on F10ing on the "return result" line.
Why is this failing, and how can I prevent it?
