And I say to ASHX for SharePoint: make me a folder.

/

Sometimes, I do get to do some on-premises farm stuff.  Because deep in my soul, I'm a hardcore dev.  Muahaha.

Scenario

In InfoPath, we want to be able to:

  • Send people to a folder within a document library, for them to upload attachments. 
  • Each form has its own unique ID, say "1234".  The folder will be <site>/Attachments/1234/
  • The folder doesn't need to be created when it's not used.  That is, it would be great to create the folder ON DEMAND
  • Finally, InfoPath is quite dumb.  It only has a hyperlink.

 

Solution

  • Create a HTTP Handler that takes this URL:  <site/sitecollection>/_layouts/InfoPathHelper/InfoPathHandler.ashx?folder=<site>/attachments/<ID>
  • Create a folder on demand, and then respond via a HTTP Redirect.

 

Steps

 

image

  1. Add a ashx handler to your SharePoint solution.  CKSDev has great template for this.
  2. Add code to ProcessRequest
    public void ProcessRequest(HttpContext context)
    {
        if (!string.IsNullOrEmpty(context.Request.QueryString["folder"]))
        {
            CreateFolderAndRedirectResponse(context);
            return;
        }
    }

  3. Add a function to check for the folder, create it if we need it, and end with a redirect.

    private void CreateFolderAndRedirectResponse(HttpContext context)
    {
        // <site-collection>/_layouts/InfoPathHelper/InfoPathHandler.ashx?folder=<site>/

        var path = context.Request.QueryString["folder"];
        var server = new Uri(SPContext.Current.Web.Url);
        var url = string.Format("{0}://{1}{2}", server.Scheme, server.Authority, path);

        // elevate permission to create the folder.
        SPSecurity.RunWithElevatedPrivileges(() =>
        {
            try
            {
                using (var site = new SPSite(url))
                {
                    using (var web = site.OpenWeb())
                    {
                        SPFolder folder = web.GetFolder(path);
                        SPFolder f = folder;
                        List<SPFolder> folders = new List<SPFolder>();
                        SPDocumentLibrary library = folder.DocumentLibrary;
                        if (library == null)
                        {
                            return;
                        }
                        while(f.Url.ToLower() != library.RootFolder.Url.ToLower()){
                            if (f.Exists || string.IsNullOrEmpty(f.Url))
                            {
                                break;
                            }

                            folders.Add(f);

                            f = f.ParentFolder;
                            if (f == null)
                            {
                                // if this happens we're in trouble
                                return;
                            }
                        }


                        if (folders.Count > 0)
                        {
                            // we are in a GET request - need to allow unsafe updates
                            web.AllowUnsafeUpdates = true;
                            folders.Reverse();
                            foreach (SPFolder f1 in folders)
                            {
                                if (!f1.Exists)
                                {
                                    f1.ParentFolder.SubFolders.Add(f1.Name);
                                }
                            }
                            web.AllowUnsafeUpdates = false;
                        }
                    }
                }
            }
            catch (Exception ex)
            {

            }
        });

        context.Response.Redirect(path, true);
    }

  4. Wait what's all the strange looking nested folder stuff?  That's right, as a bonus, if you specify nested folder within the document library, the HTTP Handler will create those too!

    folder=/attachments/1234/1235/
  5. InfoPath is super simple, just add a Hyperlink to the URL

    image

    Link to Data Source:

    concat("/_layouts/InfoPathHelper/InfoPathHandler.ashx?attachments?folder=", my:ID)

 

See it running

 

image