DocumentFileHandler.cs

using EPiServer.Web;
 
public class DocumentFileHandler : StaticFileHandler
{
    public override IAsyncResult BeginProcessRequest(HttpContext context, AsyncCallback callback, object state)
    {
        // Force Office-application to not open document directly from URL
        var extension = Path.GetExtension(context.Request.Path);
        if (OfficeExtensions.Contains(extension))
            context.Response.AppendHeader("content-disposition", "attachment");
 
        return base.BeginProcessRequest(context, callback, state);
    }
 
    protected override bool ProcessRequestInternal(HttpContext context)
    {
        if (base.ProcessRequestInternal(context))
        {
            var extension = Path.GetExtension(context.Request.Path); // override missmatch in EPiServer
            if (extension == ".pptx")
                context.Response.ContentType = "application/vnd.openxmlformats-officedocument.presentationml.presentation";
 
            var virtualFile = GenericHostingEnvironment.VirtualPathProvider.GetFile(context.Request.FilePath);
            
            // TODO: Do something with the file...we add stats for number of downloads and handle some security stuff in here....    
                
            
        }
        return false;
    }
    
    private static IEnumerable<string> OfficeExtensions
    {
        get
        {
            return new[] { ".doc", ".ppt", ".xls", ".docx", ".pptx", ".xlsx" };
        }
    }
}