Since Q2 2010 all new functionalities are listed in the control's Release Notes posted here.

• VS 2010/.NET 4 RTM support
• Added OnClientNodeAnimationEnd event
• Bug-fixes

• Replaced the RadTreeView loading icons

• No new features or bug-fixes.

• New Skin - Windows7

• New Skin - Sitefinity
• Performance optimizations on the server

• Bug-fixes

• No new features or bug-fixes.

• Full support for Google Chrome v.2
• Compatibility with Visual Studio 2010 Beta 1
• New common skin: Simple
• Added support to render properly in callback / MVC / webservice scenarios
• Bug-fixes

• Full Support for Internet Explorer 8
• Bug-fixes

• Added get_sourceNodes() method to the event arguments of the OnClientNodeDragStart and OnClientNodeDragging event handlers.
• Added new property UseHttpGet to the WebServiceSettings properties. By default its value is False.

• New client-side event added: OnClientNodeEditStart which is called as the edit begins

• Improved performance when CheckChildNodes is set to true (no more timeouts in Internet Explorer)
• Improved performance and memory usage of GetAllNodes/FindNodeByText/FindNodeByValue server-side methods

• Integrated validation for RadTreeView selection.
• Improved client-side initialization time.
• Improved WebService load on demand performance.
• Added ContentCssClass property which is applied at the DIV tag of a RadTreeNode.
• Added new server side methods FindNodeByText, FindNodeByValue which have a second argument ignoreCase which indicates whether the comparison is case-sensitive (true) or case-insensitive (false).
• Added a new server side method FindNode which has one argument match of type Predicate Generic Delegate. This method can be used to find a Node by some custom criteria.
• Added protected virtual methods for server-side events – OnNodeDataBound, OnNodeClick, etc.
• Support for server-side expressions (<%= %>) in the NodeTemplate.
• Added new client-side event: OnClientNodeDataBound
• Animations are using the jQuery library now

• Hierarchical databinding to IEnumerable via the DataFieldID/DataFieldParentID properties
• findNodeByUrl and findNodeByAbsoluteUrl client side methods of RadTreeView
• Initialization time improvement

• Added ClientChanges property to the RadTreeView class. Now client-side changes are available on the server side after postback.
• Added findControl client-side method of RadTreeNode class.

• Tri-State CheckBoxes - allows for CheckBoxes of RadTreeView to have three states: Checked, Unchecked and Indeterminate. The Tri-State behavior of RadTreeView can be controlled by the two new properties:
• TriStateCheckBoxes - enables the "Tri-State" CheckBoxes (the CheckBoxes property must be also enabled for this functionality to work)
• CheckChildNodes - when enabled all child Nodes of a Node are automatically: Checked if their parent has been Checked and Unchecked if their parent has been Unchecked

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