If I have a pdf file as a Stream, how can I write it to the response output stream?
5 Answers
Since you are using MVC, the best way is to use FileStreamResult:
return new FileStreamResult(stream, "application/pdf")
{ FileDownloadName = "file.pdf"
};Playing with Response.Write or Response.OutputStream from your controller is non-idiomatic and there's no reason to write your own ActionResult when one already exists.
One way to do it is as follows:
//assuming you have your FileStream handle already - named fs
byte[] buffer = new byte[4096];
long count = 0;
while ((count = fs.Read(buffer, 0, buffer.Length)) > 0)
{ response.OutputStream.Write(buffer, 0, count); response.Flush();
}You can also use GZIP compression to speed the transfer of the file to the client (less bytes streamed).
3In asp.net this is the way to download a pdf file
Dim MyFileStream As FileStream Dim FileSize As Long MyFileStream = New FileStream(filePath, FileMode.Open) FileSize = MyFileStream.Length Dim Buffer(CInt(FileSize)) As Byte MyFileStream.Read(Buffer, 0, CInt(FileSize)) MyFileStream.Close() Response.ContentType = "application/pdf" Response.OutputStream.Write(Buffer, 0, FileSize) Response.Flush() Response.Close()The HTTP Response is a stream exposed to you through the HttpContext.Response.OutputStream property, so if you have the PDF file in a stream you can simply copy the data from one stream to the other:
CopyStream(pdfStream, response.OutputStream);For an implementation of CopyStream see Best way to copy between two Stream instances - C#
Please try this one:
protected void Page_Load(object sender, EventArgs e) { Context.Response.Buffer = false; FileStream inStr = null; byte[] buffer = new byte[1024]; long byteCount; inStr = File.OpenRead(@"C:\Users\Downloads\sample.pdf"); while ((byteCount = inStr.Read(buffer, 0, buffer.Length)) > 0) { if (Context.Response.IsClientConnected) { Context.Response.ContentType = "application/pdf"; Context.Response.OutputStream.Write(buffer, 0, buffer.Length); Context.Response.Flush(); } } }
