In asp:treeview control such a flexibility is been provided. Please read the following paragraph.
Customizing the Appearance of the TreeView Control
The TreeView control provides ImageUrl properties such as RootNodeImageUrl, ParentNodeImageUrl, and LeafNodeImageUrl. These custom images are rendered to the left of the node's text. You can override the default image for the node type using the ImageUrl property. The TreeView control also provides CollapseImageUrl and ExpandImageUrl properties for the expanded and collapsed indicators. These are usually represented by plus and minus icons. There is also a property named NoExpandImageUrl that can be used for rendering an image for nodes which have no children. You can turn off the default image using the ShowExpandCollapseboolean property.
In addition to custom images, the TreeView control also supports TreeNodeStyle properties for each node types. These style properties override the NodeStyle property, which applies to all node types. A node can also have a different style applied when it is selected. When Selected property is set to true, the node is selected and the SelectedNodeStyle properties overrides any corresponding unselected style properties for the selected node. It is also possible for you to render check boxes between the node and image by setting the ShowCheckBoxes property to a boolean value.
Why the same flexible support has not been provided here?
Anybody please provide me a sample where in I can change image URL instead of Plus and Minus symbol in the tree.
Telerik admin please answer my query.