Impersonation for SharePoint 2010 LINQ to DataContext

Impersonation in SharePoint is not really the hardest to do. However the C# code snippet below was sort of new for me. In order to obtain impersonation for a DataContext, that was something.

Impersonation for the ClientContext … but the LINQ DataContext is constructed in another way… and by default using the current user… regardless the user you’ve set in SPContext.

So… here it is.


strUrl = SPContext.Current.Web.Url;

HttpContext backupContext = HttpContext.Current;
SPUserToken userToken = null;
  userToken =

  // if there is a SPContext make it is as null so LINQ won’t execute under current context
if (SPContext.Current != null)   HttpContext.Current = null;

  SPSecurity.RunWithElevatedPrivileges(delegate() {
    using (SPSite oSite = newSPSite(strUrl, userToken)) {
      using (SPWeb oWeb = oSite.OpenWeb()) {
                               // creating a new HttpContext under elevated permission and
             // setting it as current control context web,
             // because of this the code will be running under elevated permission.

        HttpRequest httpRequest = newHttpRequest(“”, oWeb.Url, “”);
        HttpContext.Current = newHttpContext(httpRequest, new HttpResponse(new System.IO.StringWriter()));
SPControl.SetContextWeb(HttpContext.Current, oWeb);

        using (SomeDataContext dc = SomeDataContext(oWeb.Url)) 
          var comments = from c in dc.SomeDataContext
                         where c.Var1 == someVariable 
select c;


catch (Exception ex) {}
finally {
   // make sure that you are setting the actual SPContext back
after your operation and make SharePoint happy J

   if (SPContext.Current != nullHttpContext.Current = backupContext;


Search SharePoint 2010 Managed Metadata Terms with an Ampersand

Already struggling with the poor functionality of the web service interface of the Taxonomy web service of SharePoint 2010, I stumbled upon another challenge.

I was building a MS CRM 2011 Plugin that populates the SharePoint Term Store using the Taxonomy web service (http://<sharepointurl>/_vti_bin/TaxonomyClientService.asmx).
The first problem was the poor functionality of the web service like being unable to add Labels to Terms.
This cannot be fixed worked around.

Then I had to query SharePoint for a Term that contained an ampersand.
Adding the Term was not a problem when the XML was escaped properly.

string _newterm = “V&D”;

_newterm = _newterm.Replace(“&”, “&amp;”).Replace(“<“, “&lt;”).Replace(“>”, “&gt;”).Replace(“\””, “&quot;”).Replace(“‘”, “&apos;”);


But when the SharePoint is queried for a certain Term… it works slightly different.

The TermStore can be queried for example using “GetTermsByLable()”


string TermXml = SPTaxService.GetTermsByLabel(TermLabel,







When you send use the TaxonomyClientService.asmx, the service will not find your term, even though when you created it you used the exact same string.

The reason is that an & will be stored by SharePoint as \uFF06

So when you wanna search for a Term, make sure you replace the ampersand… like…


string XmlTerm = “<newTerms><newTerm label=\”” + _newterm.Replace(“&”, “\uFF06”) + “\” clientId=\”1\” parentTermId=\”” + Guid.Empty + “\”></newTerm></newTerms>”);


The weird thing is, that the VS2010 Debugger still will show you the &amp;
The result from SharePoint is the right one…

So …replacing the & with &amp; does not work..!

Disclose MS CRM Online 2011 data in SharePoint 2010 Online

Thanks to LightningTools following blog post, I was able to quickly disclose CRM Online data is SharePoint Online.
Check out this post.

I am working myself working on the post of connecting to SharePoint 2010 Online from MS CRM 2010 Workflow or Plugin Assembly. The workflow assembly is not supported in MS CRM 2011 Online just yet… but the beta of RU8 is released. The wait is for the RU for MS CRM 2011 Online.

Check out my blog… I will post the solution shortly.

JQuery Mobile Web Client on SharePoint – The Source Code

After numerous requests of publishing the source code of my demo as showed before in JQuery Mobile Web Client on SharePoint enabled I have decided to do so.
You lucky bastards… from the goodness of my hart… and for the good of community… and for world peace.

Please be aware that the solution has not left the alpha stage.
Download the code here … SharePoint4Mobile… this is a .DOC file, cause WP didn’t allow me to upload an archive.
So …  rename the download from .DOC to .ZIP and you’ll be all set.

Things you wanna know:

  • It was developed against SharePoint 2007 in an BPOS environemnt… so you come across some BPOS specific tag in the ASPX  pages.
  • It is mainly JavaScript, cause of the BPOS SharePoint 2007 restrictions… you can make this work using .NET better and faster I’ll bet.
  • An important component I used was the 2008 SPAPI by Darren Johnstone (

Good luck and feel free to let me know what the experiences were with this piece of code.
I’m allways open for feedback.


You may wonder why I stopped developing futher.
This has a fairly simple reason.

My goal was developing an App that enabled a user on at least iPhone or iPad to not just Open and Edit MS Office files… but Save modified files back to SharePoint.
This last feature … saving changed files back to SharePoint – is not possible with iPhone or iPad.
Read one of many articles stating what Apple had NOT done to to leverage SharePoint functionality with an iPhone or iPad.


Pass a ListItemId to SharePoint workflow

In SharePoint Designer 2007 open the page where an action is needed.

Right click the control the wher you want to start the workflow from… click Form Actions.

Add Custom Action and click Settings and the Workflow Wizard will start.

Click Variables and add a variable called something like MyListItemId.

Finish the workflow and see that the code around your control will be updated somewhat like this:

<a href=”javascript: {ddwrt:GenFireServerEvent(‘__workflowStart={{FA532C23-6F80-4266-868D-1EBC219A7E11},New,{8F0B8599-4B45-421A-A4A2-9BD2817078DE},}’)}”>


Here’s what you need to do to pass the variable MyListItemId

<a href=”javascript: {ddwrt:GenFireServerEvent(concat(‘__workflowStart={{FA532C23-6F80-4266-868D-1EBC219A7E11},New,{8F0B8599-4B45-421A-A4A2-9BD2817078DE},MyListItemId=’,@ID, ‘}’))}”>



SharePoint, Remote BLOB Storage (RBS), External BLOB Storage (EBS) and FILESTREAM

Finding #1: Remote Blob Storage RBS is recommended for SharePoint 2010 in conjunction with SQL Server 2008 R2. 

Finding #2: I don’t need FILESTREAM when I want use RBS. I can use FILESTREAM in conjunction with RBS though.




On Microsofts deprecation list



BLOB Store scope

Per Content DB

Entire farm

BLOB Storage Providers

More than one

Just one

Just for informational purposes, a high level architectural difference between RBS and EBS is that RBS is implemented by SQL Server 2008 R2 and EBS is implemented from a hotfix for MOSS 2007 in SP1 and is part of the SharePoint stack. EBS is still supported but is on the deprecation list.

For RBS, out-of-the-box you get a FILESTREAM provider from Microsoft which allows you to store blobs to disk drives (i.e. c:\myblobstore). It is important to note that SharePoint 2010 doesn’t know (and doesn’t care) that BLOBs are not in the database. That is the provider’s job. Third party vendors will surely release other providers, think storage in the cloud, NAS, other storage mechanisms. So if you need something more than the FILESTREAM provider from Microsoft, you are looking to the third party market.

What is Remote BLOB Storage?

A new feature in SQL Server 2008 R2 is Remote Blob Storage (RBS) which allows admins to setup SQL to save data that would normally go into a BLOB field to be stored outside the database using an RBS provider. This provider could store data on a cheaper disk solution (compared to the expensive disk solutions usually selected for SQL Server), to a SAN or maybe even into the cloud… it really doesn’t matter where. The point is that BLOBs can be kept out of a SQL Server DB.

For SharePoint this has big implications because as a document/attachment centric product, it stores a LOT of data in BLOBs generating large content databases. Before this feature became available in SQL 2008 R2 RBS was pretty much impossible. Some like External Blob Storage (EBS) was just not recommended. SharePoint 2010 when combined with SQL Server 2008 R2 allows admins to do RBS, keeping only metadata in de content DBs and keep the BLOBs out. This is a decisions not to be taken lightly.

First think about backup & restore policy. Additional backups are needed for the remotely stored BLOBs. Those who are looking to gain from RBS are large SharePoint implementations, high investment and usage. Third party vendors of backup software who support RBS therefor have an edge.

When to use Remote BLOB Storage

  • RBS is typically recommended in the case where the content databases are 4 gigabytes (4 GB) or larger.
  • When the number and the file size get bigger and bigger.
  • Intelligent backup and restore mechanisms are in place that support RBS.

When to use FILESTREAM

In SQL Server, BLOBs can be standard varbinary(max) data that stores the data in tables, or FILESTREAM varbinary(max) objects that store the data in the file system. The size and use of the data determines whether you should use database storage or file system storage. If the following conditions are true, you should consider using FILESTREAM:

  • Objects that are being stored are, on average, larger than 1 MB.
  • Fast read access is important.
  • You are developing applications that use a middle tier for application logic.

For smaller objects, storing varbinary(max) BLOBs in the database often provides better streaming performance.

Comparison point

Storage solution

File server / file system

SQL Server (using varbinary(max))


Maximum BLOB size

NTFS volume size

2 GB – 1 bytes

NTFS volume size

Streaming performance of large BLOBs





Manual ACLs


Integrated + automatic ACLs

Cost per GB








Integration with structured data


Data-level consistency

Data-level consistency

Application development and deployment

More complex

More simple

More simple

Recovery from data fragmentation




Performance of frequent small updates




Table 1: Comparison of BLOB Storage Technologies Before SQL Server 2008

Figure #1: Read performance of various BLOB sizes

Find more info on FILESTREAM here and here.

Searching SharePoint from Windows7 Windows Explorer

In Windows7 you can create custom search connectors to OpenSearch search engines.

And YES… SharePoint 2007 en 2010 publish OpenSearch standard search engines.

It is really simple to create a connector to SharePoint.

  1. Open Notepad and copy in the XML below
  2. Replace the areas in red with your SharePoint Search Center information.  Be sure to only replace just the part of the URL that gets to your Search Center:  e.g.  
  3. Change the scope if you want:  e.g.  &amp;s=Intranet  or  &amp;s=All%20Sites  or even  &amp;s=People
  4. Save the file to your Desktop as:    SearchMySharePointSite.osdx
  5. Double click the file to install the Search Connector.  (it will install to your “Searches” directory  e.g.   c:\Users\<username>\Searches

And if you don´t have enough connectors… here is the rest of them

Amazon, DeviantArt, eBay, Flickr, Google Blogs, Google News, Live Search, MSN Search, Redmond Pie, Wikipedia, Yahoo and YouTube


<?xml version=”1.0″ encoding=”UTF-8″?>
<OpenSearchDescription xmlns=”” xmlns:ms-ose=””>
<ShortName>SharePoint Search</ShortName>
<Description>Search the SharePoint site.</Description>
<Url type=”application/rss+xml” template=”{searchTerms}&amp;s=All%20Sites“/>
<Url type=”text/html” template=”{searchTerms}&amp;s=All%20Sites“/>
<ms-ose:ResultsProcessing format=”application/rss+xml”>

Information Worker VHD 2010

There’s a new Information worker are ready to be downloaded. You can find them here.

BUT…. can we I download them all the parts at once.

YEAH…. you can. Use the Akamai download manager.

The download is about 18 GB big.

This is the content :

Virtual machine “A” contains the following pre-configured software:

  1. Windows Server 2008 R2 Standard Evaluation Edition x64, running as an Active Directory Domain Controller for the “CONTOSO.COM” domain with DNS and WINS
  2. Microsoft SQL Server 2008 R2 Enterprise Edition with Analysis, Notification, and Reporting Services
  3. Microsoft Office Communication Server 2007 R2
  4. Microsoft Visual Studio 2010
  5. Microsoft SharePoint Server 2010 Enterprise Edition
  6. Microsoft Office Web Applications
  7. Microsoft FAST Search for SharePoint 2010
  8. Microsoft Project Server 2010
  9. Microsoft Office Professional Plus 2010
  10. Microsoft Visio 2010
  11. Microsoft Project 2010
  12. Microsoft Office Communicator 2007 R2

Virtual machine “B” contains the following pre-configured software:

  1. Windows Server 2008 R2 Standard Evaluation Edition x64, joined to the “CONTOSO.COM” domain
  2. Microsoft Exchange Server 2010

Active directory has been preconfigured over 200 “demo” users with metadata in an organizational structure. All of these user profiles have been imported and indexed for search within SharePoint Server 2010.
SharePoint Server 2010 has been configured in a “Complete” farm using the default SQL Server 2008 R2 instance. A default site has been created using the Team Site template at and a FAST Search Center at
As shipped virtual machine “A” requires image “B” for email. Running image “B” is optional.