jQuery Nested Accordion (Accordion inside Accordion) from database in ASP.Net

Here I have created sample that will help you out.

HTML

<div>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
    <script src="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.9/jquery-ui.js" type="text/javascript"></script>
    <link href="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.9/themes/start/jquery-ui.css"
        rel="stylesheet" type="text/css" />
    <script type="text/javascript">
        $(function () {
            $("div.accordian").accordion({
                collapsible: true,
                active: false,
                autoHeight: false
            });
        });
    </script>
    <div class="accordian">
        <asp:Repeater ID="rptAccordian" runat="server" OnItemDataBound="OnItemDataBound">
            <ItemTemplate>
                <h3>
                    <a class="" href="#">
                        <%# Eval("Title") %></a></h3>
                <div class="accordian">
                    <asp:Repeater ID="rptSubAccordian" runat="server">
                        <ItemTemplate>
                            <h3>
                                <a class="" href="#">
                                    <%#Eval("Content") %></a></h3>
                            <div>
                                <%#Eval("ContentElement") %>
                            </div>
                        </ItemTemplate>
                    </asp:Repeater>
                    <asp:HiddenField ID="hfTitle" runat="server" Value=' <%# Eval("Title") %>' />
                </div>
            </ItemTemplate>
        </asp:Repeater>
    </div>
</div>

C#

DataTable dt = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {

        dt.Columns.AddRange(new DataColumn[3] { new DataColumn("Title"), new DataColumn("Content"), new DataColumn("ContentElement") });
        dt.Rows.Add("Section 1", "This is content of Section 1.1", "<p>Element of Section 1.1</p>");
        dt.Rows.Add("Section 1", "This is content of Section 1.2", "<p>Element of Section 1.2</p>");
        dt.Rows.Add("Section 2", "This is content of Section 2.1", "<p>Element of Section 2.1</p>");
        dt.Rows.Add("Section 2", "This is content of Section 2.2", "<p>Element of Section 2.2</p>");
        dt.Rows.Add("Section 3", "This is content of Section 3.1", "<p>Element of Section 3.1</p>");
        dt.Rows.Add("Section 3", "This is content of Section 3.2", "<p>Element of Section 3.2</p>");
        dt.Rows.Add("Section 4", "This is content of Section 4.1", "<p>Element of Section 4.1</p>");
        dt.Rows.Add("Section 4", "This is content of Section 4.2", "<p>Element of Section 4.2</p>");
        DataView dv = new DataView(dt);
        DataTable distinctTitle = dv.ToTable(true, "Title");
        rptAccordian.DataSource = distinctTitle;
        rptAccordian.DataBind();
    }
}

protected void OnItemDataBound(object sender, RepeaterItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
    {
        string Title = ((HiddenField)e.Item.FindControl("hfTitle")).Value;
        var subSection = from data in dt.AsEnumerable()
                            where data["Title"].Equals(Title)
                            select data;
        Repeater rptSubAccordian = (Repeater)e.Item.FindControl("rptSubAccordian");
        rptSubAccordian.DataSource = subSection.CopyToDataTable();
        rptSubAccordian.DataBind();
    }
}

VB

Private dt As New DataTable()
Protected Sub Page_Load(sender As Object, e As EventArgs)
	If Not Me.IsPostBack Then

		dt.Columns.AddRange(New DataColumn(2) {New DataColumn("Title"), New DataColumn("Content"), New DataColumn("ContentElement")})
		dt.Rows.Add("Section 1", "This is content of Section 1.1", "<p>Element of Section 1.1</p>")
		dt.Rows.Add("Section 1", "This is content of Section 1.2", "<p>Element of Section 1.2</p>")
		dt.Rows.Add("Section 2", "This is content of Section 2.1", "<p>Element of Section 2.1</p>")
		dt.Rows.Add("Section 2", "This is content of Section 2.2", "<p>Element of Section 2.2</p>")
		dt.Rows.Add("Section 3", "This is content of Section 3.1", "<p>Element of Section 3.1</p>")
		dt.Rows.Add("Section 3", "This is content of Section 3.2", "<p>Element of Section 3.2</p>")
		dt.Rows.Add("Section 4", "This is content of Section 4.1", "<p>Element of Section 4.1</p>")
		dt.Rows.Add("Section 4", "This is content of Section 4.2", "<p>Element of Section 4.2</p>")
		Dim dv As New DataView(dt)
		Dim distinctTitle As DataTable = dv.ToTable(True, "Title")
		rptAccordian.DataSource = distinctTitle
		rptAccordian.DataBind()
	End If
End Sub

Protected Sub OnItemDataBound(sender As Object, e As RepeaterItemEventArgs)
	If e.Item.ItemType = ListItemType.Item OrElse e.Item.ItemType = ListItemType.AlternatingItem Then
		Dim Title As String = DirectCast(e.Item.FindControl("hfTitle"), HiddenField).Value
		Dim subSection = From data In dt.AsEnumerable() Where data("Title").Equals(Title)data
		Dim rptSubAccordian As Repeater = DirectCast(e.Item.FindControl("rptSubAccordian"), Repeater)
		rptSubAccordian.DataSource = subSection.CopyToDataTable()
		rptSubAccordian.DataBind()
	End If
End Sub

Screenshot