using System;

namespace StrategyPattern1

{

// context class

public class DataImporter

{

private Parser _parser;

public void SetParser(Parser parser)

{

_parser = parser;

}

public void Execute(object data)

{

try

{

_parser.ParseData(data);

OnDataParsed(new DataParsedEventArgs() { JsonString = "JSON RESULT", Exception = null, TimeReached = DateTime.Now });

}

catch (Exception e)

{

OnDataParsed(new DataParsedEventArgs() { JsonString = string.Empty, Exception = e, TimeReached = DateTime.Now });

}

}

public event EventHandler<DataParsedEventArgs> DataParsed;

protected void OnDataParsed(DataParsedEventArgs args)

{

DataParsed?.Invoke(this, args);

}

}

// strategies interface

public abstract class Parser

{

public abstract void ParseData(object data);

}

// concrete strategy

public class DNSParser : Parser

{

public override void ParseData(object data)

{

Console.WriteLine("DNS parser goes work");

}

}

// concrete strategy

public class MVideoParser : Parser

{

public override void ParseData(object data)

{

Program.wline("MVIDEO parser goes work");

}

}

public class DataParsedEventArgs : EventArgs

{

public Exception Exception { get; set; }

public string JsonString { get; set; }

public DateTime TimeReached { get; set; }

}

//public delegate void writeline(string str);

class Program

{

public readonly Action line = () => Console.WriteLine();

public static Action<string> wline = (string s) => Console.WriteLine(s);

static void Main(string[] args)

{

wline("input parser name: ");

string parser = Console.ReadLine();

DataImporter importer = new DataImporter();

importer.DataParsed += Importer_DataParsed;

if (parser.ToLower().Contains("dns"))

{

importer.SetParser(new DNSParser());

}

else

{

importer.SetParser(new MVideoParser());

}

importer.Execute(null);

}

private static void Importer_DataParsed(object sender, DataParsedEventArgs e)

{

if (e.Exception == null)

{

wline($"Data was parsed by {sender.GetType().Name}, finished at {e.TimeReached.ToString("HH:mm ss")}");

}

}

}

}