How to use treeview in Sharepoint 2010 Sandbox solution?

Question

I have tried using Treeview in my Sanboxsolution webpart but the problem is that in a web page it is not loading properly. And when i click on node it gives me javascript error. For these two errors i have attached screenshots with this question for the reference.Have a look at it.

And in my aspx view i have written following code

<asp:TreeView runat="server" ID="trvComDept" ShowLines="True" ShowExpandCollapse="true" EnableClientScript="true" ImageSet="Simple">
<Nodes>
    <asp:TreeNode Text="Parent 1" Value="1">
        <asp:TreeNode Text="Child 1" Value="2"></asp:TreeNode>
        <asp:TreeNode Text="Child 2" Value="3"></asp:TreeNode>
    </asp:TreeNode>
</Nodes>
</asp:TreeView>

Webpage View

JS Error when i click on node

Updated Code Is As Below

Aspx Code :-

<asp:TreeView runat="server" ID="trvComDept" ShowLines="True" ShowExpandCollapse="true" EnableClientScript="true" ImageSet="Simple">    

C# Code :

List<string> Roots = new List<string>();
        List<string> Childs = new List<string>();

        for (int i = 0; i < 5; i++)
        {
            Roots.Add("Root" + i.ToString());
            Childs.Add("Child" + i.ToString());
        }

        foreach (string r in Roots)
        {
            TreeNode root = new TreeNode();
            root.Text = r;

            foreach (string c in Childs)
            {
                TreeNode child = new TreeNode();
                child.Text = c;
                root.ChildNodes.Add(child);
            }

            trvComDept.Nodes.Add(root);
        }

Answer 1

When you create a asp tree view in sharepoint you need to create a datasource for it. That's why you are getting the _Data error. I took a look on google for a good guide for you here:

How to use a asp tree view with SharePoint