spectre.console/examples/Console/Trees/Program.cs

namespace Spectre.Console.Examples
{
    public static class Program
    {
        public static void Main()
        {
            AnsiConsole.WriteLine();

            // Render the tree
            var tree = BuildTree();
            AnsiConsole.Render(tree);
        }

        private static Tree BuildTree()
        {
            // Create the tree
            var tree = new Tree("Root")
                .Style(Style.Parse("red"))
                .Guide(TreeGuide.Line);

            // Add some nodes
            var foo = tree.AddNode("[yellow]Foo[/]");
            var table = foo.AddNode(new Table()
                .RoundedBorder()
                .AddColumn("First")
                .AddColumn("Second")
                .AddRow("1", "2")
                .AddRow("3", "4")
                .AddRow("5", "6"));

            table.AddNode("[blue]Baz[/]");
            foo.AddNode("Qux");

            var bar = tree.AddNode("[yellow]Bar[/]");
            bar.AddNode(new Calendar(2020, 12)
                .AddCalendarEvent(2020, 12, 12)
                .HideHeader());

            // Return the tree
            return tree;
        }
    }
}