Hello,

You can use a recursive function to get all the subitems, for example:

List<string> allSubItems = new List<string>();

private void XamMenuItem_SubmenuOpened(object sender, EventArgs e)
{
    StringBuilder str = new StringBuilder();
    getSubItems((sender as XamMenuItem));

    foreach (var element in allSubItems)
        str.AppendLine(element);
    MessageBox.Show(str.ToString());
}

public void getSubItems(XamMenuItem parentItem)
{
    foreach (XamMenuItem item in parentItem.Items)
    {
        allSubItems.Add(item.Header.ToString());
        if (item.Items.Count > 0)
        {
            getSubItems(item);
        }
    }
}

You can test the code snippet in the attached sample application.

Let me know if you need any further assistance.

Sincerely,
Zhivko
Associate Software Developer