OurUmbraco/OurUmbraco.Site/Views/FileDownload.cshtml

@using OurUmbraco.Wiki.BusinessLogic
@inherits UmbracoTemplatePage
@{
    Layout = "~/Views/Master.cshtml";
    if (Request["id"] == null)
    {
        return;
    }

    int fileId;
    if (int.TryParse(Request["id"], out fileId) == false)
    {
        return;
    }

    if (fileId == 0)
    {
        return;
    }

    var wikiFile = new WikiFile(fileId);

    wikiFile.UpdateDownloadCounter(false, wikiFile.FileType == "package");
    using (var sqlHelper = umbraco.BusinessLogic.Application.SqlHelper)
    {
        var path = sqlHelper.ExecuteScalar<string>(
            "Select path from wikiFiles where id = @id;",
            sqlHelper.CreateParameter("@id", fileId));

        var file = sqlHelper.ExecuteScalar<string>(
            "Select name from wikiFiles where id = @id;",
            sqlHelper.CreateParameter("@id", fileId));

        var fileinfo = new System.IO.FileInfo(Server.MapPath(path));

        var extension = System.IO.Path.GetExtension(Server.MapPath(path));
        var type = "";
        // set known types based on file extension  
        if (extension != null)
        {
            switch (extension.ToLower())
            {
                case ".tif":
                case ".tiff":
                    type = "image/tiff";
                    break;
                case ".jpg":
                case ".jpeg":
                    type = "image/jpeg";
                    break;
                case ".gif":
                    type = "image/gif";
                    break;
                case ".docx":
                case ".doc":
                case ".rtf":
                    type = "Application/msword";
                    break;
                case ".pdf":
                    type = "Application/pdf";
                    break;
                case ".png":
                    type = "image/png";
                    break;
                case ".bmp":
                    type = "image/bmp";
                    break;
                default:
                    type = "application/octet-stream";
                    break;
            }
        }

        Response.Clear();

        Response.AddHeader("Content-Disposition", "attachment; filename= " + file.Replace(" ", "-"));
        Response.AddHeader("Content-Length", fileinfo.Length.ToString());
        Response.ContentType = type;
        Response.WriteFile(path);
    }
}