Recursive and Folder-Scoped LINQ Queries in SharePoint 2010

Introduction

As you might have experienced in SharePoint 2007, a CAML query is by default non recursive. In other words, if you execute a CAML query, you will end up with items from the list root folder. This is still the same in SharePoint 2010. You have to define extra query options as shown below in case you want to query all folders and sub folders within a list (Recursive Query):

qry.ViewAttributes = "Scope='Recursive'";

And if you want to scope your query to a certain folder:

qry.Folder = list.ParentWeb.GetFolder("Folders DocLib/2008");

What about LINQ to SharePoint?

The default behavior is the same, however if recursive querying is the desired behavior, you can use the ScopeToFolder method from your EntityList<T> object.

Note the following queries:

var q = dc.Projects.Where(p => p.DueDate < DateTime.Now.AddMonths(1));
var q = dc.Projects.ScopeToFolder("", true).Where
	(p => p.DueDate < DateTime.Now.AddMonths(1));

The first one executes against the list root folder while the second one is recursive. You might be wondering about the empty string that I’m passing to ScopeToFolder method. Well, let’s see what MSDN says about the parameters that the method expects.

public IQueryable<TEntity> ScopeToFolder( string folderUrl, bool recursive ) 

• folderUrl –> The URL of the folder
• recursive –> true to include items in subfolders; false to exclude them

That’s it, if you want to scope your LINQ query to a specific folder, pass the folder URL as the first parameter to the method & “true” if you want the recursive behavior of the query. In the second query, I just wanted the recursive behavior and I didn’t want to scope my query to any folders so I passed an empty string, this does the trick.

Hope this helps!