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How to make child node visible = false in a Treeview control

I have a window shape with a tree control. This tree view has root nodes and 2 child nodes. My requirement is that I need to hide the first child node. Is it possible to make that particular child node visible false

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3 answers

Yes, you can inherit from the node tree and create your own behavior. In this way.

public class RootNode : TreeNode
{
    public List<ChildNode> ChildNodes { get; set; }

    public RootNode()
    {
        ChildNodes = new List<ChildNode>();
    }

    public void PopulateChildren()
    {
        this.Nodes.Clear();

        var visibleNodes = 
            ChildNodes
            .Where(x => x.Visible)
            .ToArray();

        this.Nodes.AddRange(visibleNodes);
    }

    //you would use this instead of (Nodes.Add)
    public void AddNode(ChildNode node)
    {
        if (!ChildNodes.Contains(node))
        {
            node.ParentNode = this;
            ChildNodes.Add(node);
            PopulateChildren();
        }
    }

    //you would use this instead of (Nodes.Remove)
    public void RemoveNode(ChildNode node)
    {
        if (ChildNodes.Contains(node))
        {
            node.ParentNode = null;
            ChildNodes.Remove(node);
            PopulateChildren();
        }

    }
}

public class ChildNode : TreeNode
{
    public RootNode ParentNode { get; set; }
    private bool visible;
    public bool Visible { get { return visible; } set { visible = value;OnVisibleChanged(): } }
    private void OnVisibleChanged()
    {
        if (ParentNode != null)
        {
            ParentNode.PopulateChildren();
        }
    }
}
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No, it's impossible to make the node invisible. You must remove it, and not make it invisible. And later you will have to add it back to its original position.

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, - - . cookie.

    private void ManageTreeMenu()
    {
        var value = Utilities.Cookies.GetCookieValue("IsAdmin");
        bool.TryParse(value, out var isAdmin);

        var dir = Server.MapPath("~");
        File.Delete(dir + "Web.sitemap");
        if (isAdmin)
            File.Copy(dir + "WebAdmin.sitemap", dir + "/Web.sitemap");

        else
            File.Copy(dir + "WebOper.sitemap", dir + "/Web.sitemap");
    }

You will have to do this again if the user role has been changed in the program. I tested this only in Visual Studio, not in the deployed web application. Let the buyer be vigilant.

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