[c#] Writing MemoryStream to Response Object

I am using the following code to stream pptx which is in a MemoryStream object but when I open it I get Repair message in PowerPoint, what is the correct way of writing MemoryStream to Response Object?

HttpResponse response = HttpContext.Current.Response;
response.Clear();
response.AppendHeader("Content-Type", "application/vnd.openxmlformats-officedocument.presentationml.presentation");
response.AppendHeader("Content-Disposition", string.Format("attachment;filename={0}.pptx;", getLegalFileName(CurrentPresentation.Presentation_NM)));                
response.BinaryWrite(masterPresentation.ToArray());
response.End();

I tried all variants of end, close, flush, and System.Web.HttpContext.Current.ApplicationInstance.CompleteRequest() and none of them worked.

Then I added the content length to the header: Response.AddHeader("Content-Length", asset.File_Size.ToString());

In this example asset is a class that has a Int32 called File_Size

This worked for me and nothing else did.

Instead of creating the PowerPoint presentation in a MemoryStream write it directly to the Response.OutputStream. This way you don't need to be wasting any memory on the sever as the component will be directly streaming the output to the network socket stream. So instead of passing a MemoryStream to the function that is generating this presentation simply pass the Response.OutputStream.

The problem for me was that my stream was not set to the origin before download.

Response.Clear();
Response.ContentType = "Application/msword";
Response.AddHeader("Content-Disposition", "attachment; filename=myfile.docx");

//ADDED THIS LINE
myMemoryStream.Seek(0,SeekOrigin.Begin);

myMemoryStream.WriteTo(Response.OutputStream); 
Response.Flush();
Response.Close();

Try with this

Response.Clear();
Response.AppendHeader("Content-Type", "application/vnd.openxmlformats-officedocument.presentationml.presentation");
Response.AppendHeader("Content-Disposition", string.Format("attachment;filename={0}.pptx;", getLegalFileName(CurrentPresentation.Presentation_NM)));
Response.Flush();                
Response.BinaryWrite(masterPresentation.ToArray());
Response.End();

I had the same issue. try this: copy to MemoryStream -> delete file -> download.

string absolutePath = "~/your path";
try {
    //copy to MemoryStream
    MemoryStream ms = new MemoryStream();
    using (FileStream fs = File.OpenRead(Server.MapPath(absolutePath))) 
    { 
        fs.CopyTo(ms); 
    }

    //Delete file
    if(File.Exists(Server.MapPath(absolutePath)))
       File.Delete(Server.MapPath(absolutePath))

    //Download file
    Response.Clear()
    Response.ContentType = "image/jpg";
    Response.AddHeader("Content-Disposition", "attachment;filename=\"" + absolutePath + "\"");
    Response.BinaryWrite(ms.ToArray())
}
catch {}

Response.End();

First We Need To Write into our Memory Stream and then with the help of Memory Stream method "WriteTo" we can write to the Response of the Page as shown in the below code.

   MemoryStream filecontent = null;
   filecontent =//CommonUtility.ExportToPdf(inputXMLtoXSLT);(This will be your MemeoryStream Content)
   Response.ContentType = "image/pdf";
   string headerValue = string.Format("attachment; filename={0}", formName.ToUpper() + ".pdf");
   Response.AppendHeader("Content-Disposition", headerValue);

   filecontent.WriteTo(Response.OutputStream);

   Response.End();

FormName is the fileName given,This code will make the generated PDF file downloadable by invoking a PopUp.

Assuming you can get a Stream, FileStream or MemoryStream for instance, you can do this:

Stream file = [Some Code that Gets you a stream];
var filename = [The name of the file you want to user to download/see];

if (file != null && file.CanRead)
{
    context.Response.AddHeader("Content-Disposition", "attachment; filename=\"" + filename + "\"");
    context.Response.ContentType = "application/octet-stream";
    context.Response.ClearContent();
    file.CopyTo(context.Response.OutputStream);
}

Thats a copy and paste from some of my working code, so the content type might not be what youre looking for, but writing the stream to the response is the trick on the last line.