Creating Nodes at Runtime

• Dec 17, 2020
• 2 minutes to read

In Unbound Mode the ASPxTreeView allows you to create nodes with specified settings at runtime, using the TreeViewNodeCollection.Add methods. You can create all the nodes at one time, or create only root nodes initially, and then provide child nodes dynamically on demand, by handling an event.

The following code shows how to populate an ASPxTreeView control with nodes manually, in unbound mode. New nodes are added to the ASPxTreeView via the Add method.

This example shows how to create a simple tree when the ASPxTreeView functions in unbound mode. New nodes are added to the ASPxTreeView via the TreeViewNodeCollection.Add method.

The image below shows the result:

Default.aspx

<dx:ASPxTreeView ID="ASPxTreeView1" runat="server" AllowSelectNode="True">
</dx:ASPxTreeView>
<br />
<dx:ASPxTextBox ID="ASPxTextBox1" runat="server">
</dx:ASPxTextBox>
<br />
<dx:ASPxButton ID="ASPxButton1" runat="server" OnClick="ASPxButton1_Click" Text="Add Node">
</dx:ASPxButton>

Default.aspx.cs

public partial class _Default : System.Web.UI.Page {
    protected void Page_Load(object sender, EventArgs e) {
        if (!IsPostBack) {
         CreateTreeView(); 
        }
    }

    //Create treeview nodes. 
    void CreateTreeView() {
        string[] NodeNames = { "Inbox", "Outbox", "Sent Items", "Deleted Items", "Search Folder" };
        foreach (string Text in NodeNames) {
            ASPxTreeView1.Nodes.Add(Text);
        }
        ASPxTreeView1.Nodes.FindByText("Search Folder").Nodes.Add("Categorized Mail");

    }
    //Add a new child node to the selected node.
    protected void ASPxButton1_Click(object sender, EventArgs e) {
        if ((ASPxTreeView1.SelectedNode != null) && (ASPxTextBox1.Text != "")) {
            ASPxTreeView1.SelectedNode.Nodes.Add(ASPxTextBox1.Text);
        }
    }

}