Refresh Treenode parent to show most current child nodes

I am able to select and expand to a particular tree node programmatically, but unable to refresh it to reflect most current data in the table. Is there Treeview1.Refresh() method ? or something like that to effect? any help will be appreciated. I have a treeview and I am adding child nodes to a parent node by having the user enter data and click on a button. After that insert into the table is done, I want the parent node to refresh and show all child entries.

  protected void PopulateNode(Object sender, TreeNodeEventArgs e)
{

    switch (e.Node.Depth)
    {
        case 0:
            PopulateChild(e.Node);
            break;

        default:
            //PopulateChild(e.Node);
            break;
    }

}

protected void PopulateChild(TreeNode node)
{

    DataSet ResultSet = RunQuery("Select Id From tbl");

    if (ResultSet.Tables.Count > 0)
    {
        foreach (DataRow row in ResultSet.Tables[0].Rows)
        {
            TreeNode newNode = new TreeNode();
            newNode.Text = row["Id"].ToString();
            newNode.Value = row["Id"].ToString();
            newNode.PopulateOnDemand = true;
            newNode.SelectAction = TreeNodeSelectAction.Expand;
            node.ChildNodes.Add(newNode);
        }

    }

}

DataSet RunQuery(String QueryString)
{
    String ConnectionString = "asdasdasdasd";




    OleDbConnection DBConnection = new OleDbConnection(ConnectionString);
    OleDbDataAdapter DBAdapter;
    DataSet ResultsDataSet = new DataSet();

    try
    {

        DBAdapter = new OleDbDataAdapter(QueryString, DBConnection);
        DBAdapter.Fill(ResultsDataSet)开发者_StackOverflow;


        DBConnection.Close();

    }
    catch (Exception ex)
    {


        if (DBConnection.State == ConnectionState.Open)
        {
            DBConnection.Close();
        }

    }

    return ResultsDataSet;

}

The only option is to reload the datatable and recreate the nodes as here http://www.tek-tips.com/faqs.cfm?fid=6177

The best way to work with Treeview is with XMLDataSource. You can bind TreeView with it and rebind it rather than looping through rows/cols and creating each node.

Ref: http://quickstarts.asp.net/QuickStartv20/aspnet/doc/ctrlref/navigation/treeview.aspx

This link gives you and idea to convert other datasource to XMLDataSource and then use it to bind to treeviewl:

Once you have treeview bind to xmldatasbource, you need to refresh your datasource and then treeview with DataBind().

<datasource>.DataBind()
treeview1.DataBind()

Also, set EnableCaching = false for objectdatasource.

http://forums.asp.net/p/1083582/1609724.aspx

The TreeView you are using has an event SelectedNodeChanged which is fired on whatever events are specified in the value of the TreeNodeSelectAction property of that TreeNode. In your case the value is Expand as I can see in your code.

When you expand a node the SelectedNodeChanged is fired and handled by the PopulateNode function as specified by the OnSelectedNodeChanged property that is assigned in the html.

What we can do here includes :

A- Collapse if already expanded then expand a tree node to repopulate its children ..

B- Change the TreeNodeSelectAction property value to SelectExpand. Here we've got one more case in which the node will be repopulated and that is node selection.

C- Call PopulateNode function whenever we need and assign a TreeNode object to its sender parameter and a new TreeNodeEventArgs() to its e parameter.

References:

TreeNodeSelectAction Enumeration, TreeView.TreeNodePopulate Event, TreeNode.SelectAction Property