Display Hierarchical Data?

[Clayton Garrett]

I'd like to display hierarchical data in the combobox.  Any suggestions on how to accomplish this?

Example would be:

Home
About
   Mission Statement
   Vision
Programs
   Program 1
       Requirements
       Features
   Program 2

Any help is appreciated!

Thanks,
Jason

[Serrin]

Hey Jason,

Looks like there are a few options you can go with on this...  You can put a TreeView into a combobox like in this example:

TreeView in Combo Box

Or you can do something like this example which takes data from an XML file...

<?xml version="1.0" encoding="utf-8" ?>
<Menu>
  <Home Value="1" />
  <About Value="2">
    <MissionStatement Value="3" />
    <Vision Value="4" />
  </About>
  <Programs Value="5">
    <Program1 Value="6">
      <Requirements Value="7"/>
      <Features Value="8"/>
    </Program1>
    <Program2 Value="9"/>
  </Programs>
</Menu>

And then use this code to populate the ComboBox:

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            XmlDocument MenuDoc = new XmlDocument();
            MenuDoc.Load(MapPath("xmlexample.xml"));
            RecurseNodes(MenuDoc.DocumentElement);
        }
    }

    private void RecurseNodes(XmlNode xmlNode)
    {
        // loop starts at level 0
        RecurseNodes(xmlNode, 0);
    }

    private void RecurseNodes(XmlNode xmlNode, int level)
    {
        string s;
        s = string.Format("{0} {1}", new string('-', level), xmlNode.Name);
        RadComboBox1.Items.Add(new RadComboBoxItem(s.ToString()));

        foreach (XmlNode menuChild in xmlNode.ChildNodes)
        {
            RecurseNodes(menuChild, level + 1);
        }
    }

Thanks to the MS certification book for that second way to do it. :)

-Serrin

[Clayton Garrett]

Hi Serrin,

Thanks for the quick reply!  I was trying to implement something more inline with the second solution you listed.  Any idea how I can incorporate that second solution with my code below:

       Private Sub GenerateComboBoxHierarchy()
            Dim ds As DataSet = DBObjects.SiteMapNodeCollection.GetAllAsDataSet
            ds.Relations.Add("NodeRelation", ds.Tables(0).Columns("SiteMapNodeId"), ds.Tables(0).Columns("ParentId"))

            For Each dbRow As DataRow In ds.Tables(0).Rows
                If dbRow.IsNull("ParentId") Then
                    Dim node As RadComboBoxItem = CreateNode(dbRow("Title").ToString(), dbRow("PageContentId"), IIf(dbRow("ParentId") Is Convert.DBNull, 0, dbRow("ParentId")))
                    RecursivelyPopulate(dbRow, node)
                End If
            Next

        End Sub

        Private Sub RecursivelyPopulate(ByVal dbRow As DataRow, ByVal node As RadComboBoxItem)
            For Each childRow As DataRow In dbRow.GetChildRows("NodeRelation")
                Dim childNode As RadComboBoxItem = CreateNode(String.Concat(childRow("Title").ToString()), childRow("PageContentId"), childRow("ParentId"))
                rcbExistingPages.Items.Add(childNode)
                RecursivelyPopulate(childRow, childNode)
            Next
        End Sub

        Private Function CreateNode(ByVal text As String, ByVal value As Integer, ByVal parentId As Integer) As RadComboBoxItem
            Dim node As New RadComboBoxItem(text, value)
            node.Attributes.Add("PageContentId", value)
            Return node
        End Function

[Clayton Garrett]

Serrin,

I think I figured it out:

Private Sub RecursivelyPopulate(ByVal dbRow As DataRow, ByVal node As RadComboBoxItem, ByVal level As Integer)
            For Each childRow As DataRow In dbRow.GetChildRows("NodeRelation")
                Dim s As String = String.Format("{0} {1}", New String(Chr(32), level), childRow("Title").ToString())
                Dim childNode As RadComboBoxItem = CreateNode(String.Concat(s), childRow("PageContentId"), childRow("ParentId"))
                rcbExistingPages.Items.Add(childNode)
                RecursivelyPopulate(childRow, childNode, level + 1)
            Next
End Sub