• ClientSide, this will expand the child nodes in the client itself.
• ServerSide, this will trigger a postback to load child nodes on demand.
• ServerSideCallback, this will trigger asyncronous postback to load child nodes on demand.

<obout:Tree ID="OboutTree1" CssClass="vista" Width="150px" runat="server">
    <Nodes>
        <obout:Node Text="Node 0">
                     <obout:Node Text="Node 00">
                    ...
                    </obout:Node>
        ...
        </obout:Node>
        ...
    </Nodes>
</obout:Tree>


<obout:Tree ID="OboutTree2" CssClass="vista" Width="150px" runat="server">
    <Nodes>
        <obout:Node ExpandMode="ServerSide" Text="Node 0">
            <obout:Node ExpandMode="ServerSide" Text="Node 00">
                ...
            </obout:Node>
        ...
        </obout:Node>
        ...
    </Nodes>
</obout:Tree>

<obout:Tree ID="OboutTree3" CssClass="vista" Width="150px" runat="server">
    <Nodes>
        <obout:Node ExpandMode="ServerSideCallback" Text="Node 0">
            <obout:Node ExpandMode="ServerSideCallback" Text="Node 00">
            ...
            </obout:Node>
        </obout:Node>
        ...
    </Nodes>
</obout:Tree>