ExpandDepth equivilent?

[Paul]

I'm creating a treeview via a database. Currently, only the root node is displayed when the page loads. Is there an equivilent to the Microsoft Treeview ExpandDepth so that I can display the first level underneath the root as well?

I tried expanding root node in the code behind without success. Here is my code:

<telerik:RadTreeView ID="RadTreeView1" runat="server" DataSourceID="DataMart" DataFieldID="cellkey"
    DataFieldParentID="cellparent" DataTextField="celldescriptor"
    LoadingStatusPosition="BeforeNodeText" SingleExpandPath="True">
    <CollapseAnimation Duration="100" Type="None" />
    <ExpandAnimation Duration="100" Type="None" />
</telerik:RadTreeView>
<asp:SqlDataSource ID="DataMart" runat="server" ConnectionString="<%$ ConnectionStrings:DataMart %>"
    SelectCommand="SST.PR_GET_JUPITER_TREE" SelectCommandType="StoredProcedure">
    <SelectParameters>
        <asp:Parameter DefaultValue="2" Name="Starting_Node" Type="Int32" />
    </SelectParameters>
</asp:SqlDataSource>

Thanks!

[Veselin Vasilev]

Hello Paul,

I guess you are calling the expand method before the TreeView is databound.

There are two ways to proceed:

1. Subscribe to the NodeBound event handler and set the Expanded property for the root nodes. Here is how:

protected void RadTreeView1_NodeDataBound(object sender, RadTreeNodeEventArgs e)
{
    //root nodes only
    if (e.Node.Level == 0)
    {
        e.Node.Expanded = true;
    }
}

2. Manually call the DataBind() method and then enumerate the root nodes and expand them:

protected void Page_Load(object sender, EventArgs e)
{
    RadTreeView1.DataBind();
    //enumerate the root nodes
    foreach (RadTreeNode rootNode in RadTreeView1.Nodes)
    {
        rootNode.Expanded = true;
    }
}

I hope this helps.

All the best,
Veskoni
the Telerik team

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[Paul]

Veskoni,

I did not test #1, but #2 worked perfectly for what I needed. Thanks!

Paul

[Frederik]

I know this thread is very old, but what I do using RadTreeView is you want to expand to a certain depth 'MaxDepth' which is defined elsewhere:

Protected Sub RadTreeView1_NodeDataBound(sender As Object, e As Telerik.Web.UI.RadTreeNodeEventArgs) Handles RadTreeView1.NodeDataBound
e.Node.Expanded = e.Node.Level <= MaxDepth
End Sub

It's very similar code, just a bit shorter.
First post, be gentle.