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Using Additional Columns

If you need to map additional columns from the Data Source to properties of the RadTreeView Nodes, you can use the NodeDataBound event. The event arguments passed to the event, e.Nodeand e.Node.DataItem, hold the instance of the RadTreeView Node being bound and the DataItem to which it is bound. You can map a property from the DataItem to the corresponding property of the RadTreeView Node. Be sure to cast the DataItem object to the proper data type first.

In the example below, the RadTreeView is bound to a DataTable and the DataItem is of type DataRowView. If you were binding to an array of a custom object "Employee", then the DataItem would be cast to the Employee type before using.

protected void RadTreeView1_NodeDataBound(object sender, RadTreeNodeEventArgs e) 
    e.Node.ToolTip = (e.Node.DataItem as DataRowView)["Description"].ToString(); 
Protected Sub RadTreeView1_NodeDataBound(ByVal sender As Object, ByVal e As RadTreeNodeEventArgs)
    e.Node.ToolTip = (TryCast(e.Node.DataItem, DataRowView))("Description").ToString()
End Sub 
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