MemoryStream to PDF C#

We can load, create, and export MemoryStream to PDF files in C# .NET without even touching the file system. This is possible through the MemoryStream object present inside the System.IO .NET namespace. Follow the tutorial below to find out how to export HTML to PDF in your C# project.


Step 1

1. Install IronPDF

In this tutorial, we'll be using IronPDF's C# PDF Library to save MemoryStream files to PDF in C#. You can download it free or install to Visual Studio with NuGet.


 PM > Install-Package IronPdf

How to Tutorial

2. Load a PDF from Memory

A new instance of IronPdf.PdfDocument can be initialized in any of these .NET in-memory-objects:

  • A MemoryStream
  • A FileSteam
  • Binary Data as a Byte array (byte[])

Here is an example of reading a URL directly into a stream, then saving the PDF file to disk by using C#:

/**
Load PDF from Memory
anchor-load-a-pdf-from-memory
**/
​    private void ReadViaMemStream()

​    {

​      //Conversion of the URL into PDF

​      var Renderer = new IronPdf.ChromePdfRenderer();

​      Uri url = new Uri("https://ironpdf.com/docs/questions/pdf-memory-stream/");

​      MemoryStream rend = Renderer.RenderUrlAsPdf(url).Stream; //Read stream

​      HttpContext.Current.Response.AddHeader("Content-Type", "application/pdf"); //Download

​      HttpContext.Current.Response.AddHeader("Content-Disposition", String.Format("{0}; filename=Print.pdf; size={1}", "attachment", rend.Length.ToString()));

​      // Write PDF buffer to HTTP response

​      HttpContext.Current.Response.BinaryWrite(rend.ToArray());

​      // Stop page processing

​      HttpContext.Current.Response.End();

​    }
/**
Load PDF from Memory
anchor-load-a-pdf-from-memory
**/
​    private void ReadViaMemStream()

​    {

​      //Conversion of the URL into PDF

​      var Renderer = new IronPdf.ChromePdfRenderer();

​      Uri url = new Uri("https://ironpdf.com/docs/questions/pdf-memory-stream/");

​      MemoryStream rend = Renderer.RenderUrlAsPdf(url).Stream; //Read stream

​      HttpContext.Current.Response.AddHeader("Content-Type", "application/pdf"); //Download

​      HttpContext.Current.Response.AddHeader("Content-Disposition", String.Format("{0}; filename=Print.pdf; size={1}", "attachment", rend.Length.ToString()));

​      // Write PDF buffer to HTTP response

​      HttpContext.Current.Response.BinaryWrite(rend.ToArray());

​      // Stop page processing

​      HttpContext.Current.Response.End();

​    }
'''
'''Load PDF from Memory
'''anchor-load-a-pdf-from-memory
'''*
​ Private Sub ReadViaMemStream()

​ ​ var Renderer = New IronPdf.ChromePdfRenderer()

​ Uri url = New Uri("https://ironpdf.com/docs/questions/pdf-memory-stream/")

​ MemoryStream rend = Renderer.RenderUrlAsPdf(url).Stream 'Read stream

​ HttpContext.Current.Response.AddHeader("Content-Type", "application/pdf") 'Download

​ HttpContext.Current.Response.AddHeader("Content-Disposition", String.Format("{0}; filename=Print.pdf; size={1}", "attachment", rend.Length.ToString()))

​ ​ HttpContext.Current.Response.BinaryWrite(rend.ToArray())

​ ​ HttpContext.Current.Response.End()

'INSTANT VB TODO TASK: The following line uses invalid syntax:
'​ }
VB   C#

3. Save a PDF to Memory

An IronPdf.PdfDocument can be saved directly to memory in one of 2 ways:


4. Serve a PDF to Web from Memory

To serve or export a PDF to the web, you need to send the PDF file as binary data instead of HTML. You can find out more here about saving & exporting PDF documents in C#.

Here is a quick example for MVC and ASP.NET:

4.1. Export a PDF with MVC

/**
Export PDF with MVC
anchor-export-a-pdf-with-mvc
**/

return new FileStreamResult(stream, “application/pdf”)

{

   FileDownloadName = “downloadedfile.pdf”

};
/**
Export PDF with MVC
anchor-export-a-pdf-with-mvc
**/

return new FileStreamResult(stream, “application/pdf”)

{

   FileDownloadName = “downloadedfile.pdf”

};
'''
'''Export PDF with MVC
'''anchor-export-a-pdf-with-mvc
'''*

'INSTANT VB TODO TASK: The following line uses invalid syntax:
'Return New FileStreamResult(stream, "application/pdf”) { FileDownloadName = "downloadedfile.pdf” };
VB   C#

4.1. Export a PDF with ASP.NET

/**
Export PDF with ASPNET
anchor-export-a-pdf-with-asp-net
**/
byte[] Binary = MyPDFDocument.BinaryData;

Response.Clear();

Response.ContentType = “application/octet-stream”;

Context.Response.OutputStream.Write(Binary, 0, Binary.Length);

Response.Flush();
/**
Export PDF with ASPNET
anchor-export-a-pdf-with-asp-net
**/
byte[] Binary = MyPDFDocument.BinaryData;

Response.Clear();

Response.ContentType = “application/octet-stream”;

Context.Response.OutputStream.Write(Binary, 0, Binary.Length);

Response.Flush();
'''
'''Export PDF with ASPNET
'''anchor-export-a-pdf-with-asp-net
'''*
Dim Binary() As Byte = MyPDFDocument.BinaryData

Response.Clear()

'INSTANT VB TODO TASK: The following line uses invalid syntax:
'Response.ContentType = "application/octet-stream”; Context.Response.OutputStream.Write(Binary, 0, Binary.Length); Response.Flush();
VB   C#