如何获得父母直放站的价值？

Question

我有3个嵌套的中继器：

<ul class="sub-menu">
  <asp:Repeater id="lev_1_nav" onitemdatabound="lev_1_nav_prod_dataBind" runat="server" >
    <ItemTemplate>
      <li class="nav-item"><span class="title"><%# Eval("Name") %></span>
        <ul class="sub-menu" id="sub_level_2" runat="server">
          <asp:Repeater id="level_2_nav_prod" runat="server">
            <ItemTemplate>
            <li id="li" runat="server">
                <span class="title"><%# Eval("Name") %</span>
                <ul class="sub-menu" id="sub_level_3" runat="server" visible="False">
                <asp:Repeater id="level_3_nav_prod" runat="server">
                  <ItemTemplate>
                  <li class="nav-item">
                      <span class="title"><%# Eval("Name") %></span></a>
                  </li>
                  </ItemTemplate>
                  </asp:Repeater>
              </ul>
            </li>
            </ItemTemplate>
            </asp:Repeater>
        </ul>
      </li>
    </ItemTemplate>
  </asp:Repeater>
</ul>

我正在尝试将json绑定到这些转发器。 json对象如下所示：

{
  "categories": [
    "Category1":  {
      "categories": [
        "Subcategory 1",
        "Subcategory 2": {
          "categories": [
            "Subsubcategory 1”
            "Subsubcategory 2"
          ]
        }
      ]
    }
  ]
}

对于顶级类别，我这样绑定：

Dim categories = loader.LoadFromFile(filePath)
lev_1_nav.DataSource = categories
lev_1_nav.DataBind()

这很好用，但是对于绑定子类别，我想做这样的事情：

Sub lev_1_nav_prod_dataBind(ByVal Sender As Object, ByVal e As RepeaterItemEventArgs)

    If e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem Then
        Dim rep As Repeater = e.Item.FindControl("lev_2_nav_prod")
        Dim name As String = (e.Item.Parent.Parent As RepeaterItem).DataItem("Name")
        For Each cat In categories
            If e.Item.DataItem("Name") = cat.Name Then
                rep.DataSource = cat.categories
                rep.DataBind()
            End if
        Next
    End If

End Sub

对于行Dim name As String = (e.Item.Parent.Parent As RepeaterItem).DataItem("Name")，它的意思是Value of type 'Control' cannot be converted to 'String'。尽管那是正确的，但我不确定我是否在正确的装订轨道上