System.CommandLine.Extensions

The new System.CommandLine API offers for sure more advanced command configuration and execution than the retired Microsoft.Extensions.CommandLineUtils API. But the broader set of functionality comes with the burden of more complex boilerplate code required to let the cow fly. The System.CommandLine.Extensions API adds a thin application layer to System.CommandLine which is similar to the retired API, cuts down functionality and thus brings back the simplicity.

Greeting Example

private static int Main(string[] args)
{
    var app = new CommandlineApplication();

    app.Command("greeting", "Greets the specified person.", greeting =>
    {
        greeting.Option<string>("--name", "The person´s name.", ArgumentArity.ExactlyOne)
            .Option<bool>("--polite")
            .OnExecute(async (string name, bool polite) =>
            {
                if (polite) Console.WriteLine($"Good day {name}");
                else Console.WriteLine($"Hello {name}");
                return await Task.FromResult(0);
            });
    });

    return app.Execute(args);
}

Usage

$ demo greeting --name Jon --polite