C# - System.ObectDisposedException in MemoryStream for Capacity, Length, and Position Properties - dispose

Question

When executing the code to render PDF file from Html Stream, code seems to be executing fine, but PDF is not generated.
When debugging through the code, it seems that everything works just fine until I do not start looking into MemoryStream object properties and notice the following under MemoryStream object:
This is the code:
public partial class WriteNotes : System.Web.UI.Page
{
...
protected override void Render(System.Web.UI.HtmlTextWriter writer)
{
...
using (System.IO.MemoryStream printStream = new System.IO.MemoryStream())
using (System.IO.StreamWriter printStreamWriter = new System.IO.StreamWriter(printStream))
using (System.Web.UI.HtmlTextWriter printWriter = new System.Web.UI.HtmlTextWriter(printStreamWriter))
{
base.Render(printWriter);
printWriter.Flush();
using (System.IO.StreamReader myStreamReader = new System.IO.StreamReader(printStream))
{
myStreamReader.BaseStream.Position = 0;
Document pdfDocument = pdfConverter.GetPdfDocumentObjectFromHtmlStream(myStreamReader.BaseStream, System.Text.Encoding.Default, HttpContext.Current.Request.Url.ToString().Replace(HttpContext.Current.Request.Url.PathAndQuery, "/"));
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.ContentType = "application/pdf";
pdfDocument.Save(HttpContext.Current.Response.OutputStream);
HttpContext.Current.Response.Flush();
HttpContext.Current.Response.End();
}
}
}
...
}
Executing the following line of code produces the described exception for MemoryStream.
Document pdfDocument = pdfConverter.GetPdfDocumentObjectFromHtmlStream(myStreamReader.BaseStream, System.Text.Encoding.Default, HttpContext.Current.Request.Url.ToString().Replace(HttpContext.Current.Request.Url.PathAndQuery, "/"));
The same kind of exception happens if I do not use Disposable Pattern.
The same code is in production and works fine.
What can be the reason?

Answer 1

Sure enough, found it. Read the documentation here:
PdfConverter.GetPdfDocumentObjectFromHtmlStream(htmlStream, streamEncoding)
In a nutshell it says to close the document object which you are not doing in your code above.
PdfDocument.Close()
States it here too, always call method close on the document object once you are done with it. Try this updated code.
Also add the library you are using next time if you happen to know it. Some answers can be found right in the documentation (not all the time of course).
public partial class WriteNotes : System.Web.UI.Page
{
...
protected override void Render(System.Web.UI.HtmlTextWriter writer)
{
...
using (System.IO.MemoryStream printStream = new System.IO.MemoryStream())
using (System.IO.StreamWriter printStreamWriter = new System.IO.StreamWriter(printStream))
using (System.Web.UI.HtmlTextWriter printWriter = new System.Web.UI.HtmlTextWriter(printStreamWriter))
{
base.Render(printWriter);
printWriter.Flush();
using (System.IO.StreamReader myStreamReader = new System.IO.StreamReader(printStream))
{
myStreamReader.BaseStream.Position = 0;
Document pdfDocument = pdfConverter.GetPdfDocumentObjectFromHtmlStream(myStreamReader.BaseStream, System.Text.Encoding.Default, HttpContext.Current.Request.Url.ToString().Replace(HttpContext.Current.Request.Url.PathAndQuery, "/"));
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.ContentType = "application/pdf";
pdfDocument.Save(HttpContext.Current.Response.OutputStream);
pdfDocument.Close(); // add this line and see what happens
HttpContext.Current.Response.Flush();
HttpContext.Current.Response.End();
}
}
}
...
}