// @nuget: CommandLineParser -Version 2.8.0

​

​

using System;

using System.Collections.Generic;

using CommandLine;

using CommandLine.Text;

public class Program

{   

    public static void Main()

    {   

         var args ="--help".Split();

        StartUp(args);

   }

     static void StartUp(string[] args)

        {

            var parser = new CommandLine.Parser(with=>  with.HelpWriter=null);

            var parserResult = parser.ParseArguments<Options>(args);

            parserResult

             .WithParsed<Options>(options => Run(options))

             .WithNotParsed(errs=> DisplayHelp(parserResult,errs));

        }

     static void DisplayHelp<T>(ParserResult<T> result,IEnumerable< Error> errs)

    {

        var helpText= HelpText.AutoBuild(result, h =>

         {

             h.AdditionalNewLineAfterOption=false; //remove the extra newline between options

             h.Heading ="Myapp 2.0.0-beta"; //change header

             h.Copyright="Copyright (c) 2019 Global.com"; //change copyrigt text

            return HelpText.DefaultParsingErrorsHandler(result, h);

         } , e=>e); 

          Console.WriteLine(helpText);

    }

     static void Run(Options options)

    {

           //do stuff      

    }

}

​

class Options

{

  [Option('r', "read", Required = false, HelpText = "Input files to be processed.")]

  public IEnumerable<string> InputFiles { get; set; }

​

  // Omitting long name, defaults to name of property, ie "--verbose"

  [Option(

    Default = false,

    HelpText = "Prints all messages to standard output.")]

  public bool Verbose { get; set; }

  [Option("stdin",

    Default = false,

    HelpText = "Read from stdin")]

  public bool stdin { get; set; }

​

  [Value(0, MetaName = "offset", HelpText = "File offset.")]

  public long? Offset { get; set; }

​

​

}