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Expanding Nodes on a Single Click

By default, RadTreeView expands a node by clicking the plus button or by double clicking the parent node. You can change this behavior by handling the OnClientNodeClicked event, getting a reference to the clicked on node and calling the RadTreeNode toggle() function. You can tailor this behavior to only occur when particular nodes are clicked by checking the node text, value, category or attributes.

<telerik:RadTreeView RenderMode="Lightweight" ID="RadTreeView1" runat="server" OnClientNodeClicked="ClientNodeClicked">
    <Nodes>
        <telerik:RadTreeNode runat="server" ExpandMode="ClientSide" Text="Search" ImageUrl="~/images/search.ico"
            Expanded="True" Value="1">
            <Nodes>
                <telerik:RadTreeNode runat="server" ExpandMode="ClientSide" Text="Documents" ImageUrl="~/images/search4doc.ico"
                    Category="NoDragging">
                </telerik:RadTreeNode>
                <telerik:RadTreeNode runat="server" ExpandMode="ClientSide" Text="Files" ImageUrl="~/images/search4Files.ico">
                </telerik:RadTreeNode>
                <telerik:RadTreeNode runat="server" ExpandMode="ClientSide" Text="People" ImageUrl="~/images/search4people.ico">
                </telerik:RadTreeNode>
                <telerik:RadTreeNode runat="server" ExpandMode="ClientSide" Text="Printers" ImageUrl="~/images/search4printer.ico">
                </telerik:RadTreeNode>
                <telerik:RadTreeNode runat="server" ExpandMode="ClientSide" Text="Web" ImageUrl="~/images/searchweb.ico"
                    Category="NonCheckable">
                </telerik:RadTreeNode>
                <telerik:RadTreeNode runat="server" ExpandMode="ServerSideCallback" Text="Recent Searches">
                </telerik:RadTreeNode>
                <telerik:RadTreeNode runat="server" ExpandMode="ServerSideCallback" Text="Network Locations"
                    ContextMenuID="SearchMenu">
                </telerik:RadTreeNode>
            </Nodes>
        </telerik:RadTreeNode>
    </Nodes>
</telerik:RadTreeView>
function ClientNodeClicked(sender, eventArgs) {
    var node = eventArgs.get_node();
    node.toggle();
}

See Also

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