Since my last post I have made a few modifications
to the
PDF generation, the main one being that the files are now dynamically renamed so that they reflect the name of the case study instead of all being called
PDF.PDF which was not a very helpful filename, I just wanted
to get something live last week, so decided that something was better than nothing :)The issue with the filenames comes down
to the way that the
PDF's are being generated by using an alternative template in Umbraco, this means that all you need
to do is add " /pdf "
to the end of a case study URL and it will create a
PDF version of the case study. The down side is that your browser will merrily download the file and save it as
PDF.PDF because that is the name of the last part of the URL.What you need
to do is set the content-disposition header
to be equal
to the name you would like the file use, Darren Ferguson mentioned this on the Change the name of the
PDF forum post.We have used the same technique for downloading dynamically generated excel files, so I thought it would be useful
to create a small macro
to set both this header and also
to set the caching headers
to prevent any caching issues, I think in the past we have experienced all possible issues, including various issues where IE behaves differently
to other browsers when you are using SSL and so the below code should work in all situations!The template for the
PDF alternative template is very simple:<%@ Master Language="C#" MasterPageFile="~/umbraco/masterpages/default.master" AutoEventWireup="true" %><asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolderDefault" runat="server"> <umbraco:Macro Alias="PDFHeaders" runat="server"></umbraco:Macro> <umbraco:Macro xsl="FO-CaseStudy.xslt" Alias="PDFXSLFO" runat="server"></umbraco:Macro></asp:Content>The following code snippet is the XSLT macro that simply creates our file name and then passes the file name into the helper function:<xsl:template match="/"> <xsl:variable name="fileName"> <xsl:text>Vizioz_</xsl:text> <xsl:value-of select="$currentPage/@nodeName" /> <xsl:text>_case_study.pdf</xsl:text> </xsl:variable> <xsl:value-of select="Vizioz.Helper:AddDocumentDownloadHeaders('application/pdf', $fileName)"/> </xsl:template>And the following code is the helper function that clears the current response and adds all the appropriate headers:public static void AddDocumentDownloadHeaders(string contentType, string fileName){ HttpResponse response = HttpContext.Current.Response; HttpRequest request = HttpContext.Current.Request; response.Clear(); response.ClearHeaders(); if (request.IsSecureConnection & request.Browser.Browser == "IE") { // Don't use the caching headers if the browser is IE and it's a secure connection // see: http://support.microsoft.com/kb/323308 } else { // force not using the cache response.AppendHeader("Cache-Control", "no-cache"); response.AppendHeader("Cache-Control", "private"); response.AppendHeader("Cache-Control", "no-store"); response.AppendHeader("Cache-Control", "must-revalidate"); response.AppendHeader("Cache-Control", "max-stale=0"); response.AppendHeader("Cache-Control", "post-check=0"); response.AppendHeader("Cache-Control", "pre-check=0"); response.AppendHeader("Pragma", "no-cache"); response.Cache.SetCacheability(HttpCacheability.NoCache); response.Cache.SetNoStore(); response.Cache.SetExpires(DateTime.UtcNow.AddMinutes(-1)); } response.AppendHeader("Expires", DateTime.Now.AddMinutes(-1).ToLongDateString()); response.AppendHeader("Keep-Alive", "timeout=3, max=993"); response.AddHeader("content-disposition", "attachment; filename=\"" + fileName + "\""); response.ContentType = contentType;}I will write another blog soon with some more details about XSL-FO and how
to create the
PDF's dynamically.Please do re-tweet if you find this interest :)
