Empty content on the downloaded PDF using itextsharp in WebAPI 2 response

Question

public IHttpActionResult DownloadPDF()
{
    var stream = CreatePdf();

    return ResponseMessage(new HttpResponseMessage
    {
        Content = new StreamContent(stream)
        {
            Headers =
            {
                ContentType = new MediaTypeHeaderValue("application/pdf"),
                ContentDisposition = new ContentDispositionHeaderValue("attachment")
                {
                    FileName = "myfile.pdf"
                }
            }
        },
        StatusCode = HttpStatusCode.OK
    });
}
Here is the CreatePdf method:

private Stream CreatePdf()
{
    using (var document = new Document(PageSize.A4, 50, 50, 25, 25))
    {
        var output = new MemoryStream();

        var writer = PdfWriter.GetInstance(document, output);
        writer.CloseStream = false;

        document.Open();
        document.Add(new Paragraph("Hello World"));
        document.Close();

        output.Seek(0, SeekOrigin.Begin);

        return output;
    }
}

I can able to download the PDF but the context is empty. Here I am using memory stream and I also tried with file stream its downloading in the respective folder but if I tried to open the downloaded file then also the content is empty. Can anyone help me what I'm missing here?

Also closing the document should be the last thing before returning the output — Nkosi, Dec 08 '17 at 11:24

Nkosi · Answer 1 · 2017-12-08T13:06:07.107

Here is an approach that usually works for me when using Web API

private byte[] CreatePdf() {
    var buffer = new byte[0];
    //stream to hold output data
    var output = new MemoryStream();
    //creation of a document-object
    using (var document = new Document(PageSize.A4, 50, 50, 25, 25)) {
        //create a writer that listens to the document
        // and directs a PDF-stream to output stream
        var writer = PdfWriter.GetInstance(document, output);

        //open the document
        document.Open();

        // Create a page in the document
        document.NewPage();

        // Get the top layer to write some text
        var pdfContentBytes = writer.DirectContent;
        pdfContentBytes.BeginText();

        //add content to page
        document.Add(new Paragraph("Hello World"));

        //done writing text
        pdfContentBytes.EndText();

        // make sure any data in the buffer is written to the output stream
        writer.Flush();

        document.Close();
    }    
    buffer = output.GetBuffer();
    return buffer;
}

And then in the action

public IHttpActionResult DownloadPDF() {
    var buffer = CreatePdf();

    return ResponseMessage(new HttpResponseMessage {
        Content = new StreamContent(new MemoryStream(buffer)) {
            Headers = {
                ContentType = new MediaTypeHeaderValue("application/pdf"),
                ContentDisposition = new ContentDispositionHeaderValue("attachment") {
                    FileName = "myfile.pdf"
                }
            }
        },
        StatusCode = HttpStatusCode.OK
    });
}

Thanks for your comments. But now, I can't even open the file the following Error "Failed to load PDF document." i'm getting. — Sabarish, Dec 08 '17 at 12:59
Now, again the previous issue, I don't see the content of the PDF. it's empty here. — Sabarish, Dec 08 '17 at 14:10

Empty content on the downloaded PDF using itextsharp in WebAPI 2 response

1 Answers1