Program.cs

using System;
using ATB_ChainPattern.BaseHandlers;
using ATB_ChainPattern.ConcreteHandlers;

namespace ATB_ChainPattern
{
    // Client Code
    class Program
    {
        static void Main(string[] args)
        {
            // Create handlers
            var stockHandler = new StockHandlerBase();
            var cryptoHandler = new CryptoHandlerBase();

            // Set up the chain
            stockHandler.SetSuccessor(cryptoHandler);

            // Client requests analysis of Tesla Stock
            stockHandler.AnalyzeProduct("Tesla Stock");

            // Client requests analysis of Bitcoin
            stockHandler.AnalyzeProduct("Bitcoin");
        }
    }
}