How to download a PowerPoint file using C#

Introduction

Recently I had to write a few lines of code to download a PowerPoint presentation file from one of my ASP.NET websites. I would like to share the block of code I used for this purpose.

if (File.Exists(Server.MapPath(file)))
{			
   Response.ClearHeaders();
   Response.Clear();			
   Response.ContentType = "application/x-mspowerpoint";
   Response.AddHeader("Content-Disposition", "attachment; filename=" + file);
   Response.WriteFile(Server.MapPath(file));
   Response.Flush();
}

Here Response.ContentType should be set correctly. I have used  "application/x-mspowerpoint" for PowerPoint. You need to set the correct ContentType. For example, for MS Word you should set application/msword, for a GIF image you should set image/gif, for PDF you should set application/pdf, etc.

Here is the reference to set Response.ContentType :

• http://msdn.microsoft.com/en-us/library/ms775147.aspx 
• http://forums.asp.net/t/1159236.aspx 

Another important information: 

To have it work correctly in IE you need to write the code in the Page_load event. So, for this you may create a page Download.aspx and redirect to that page when you click the Download button with file information in the querystring. 

Hope it helps.