Abstract Factory design pattern

Abstract Factory Pattern provides a way to encapsulate a group of individual factories that have a common theme.

In the scenario, where if there is two or more factory class with common theme (like private or public sector.

UML Diagram script from

[<frame>Abstract factory design pattern|
  [client] o- [<abstract>InvestmentFactory|  GetProduct(string productType)]
  [InvestmentFactory] <:-- [PrivateSectorFactory|  GetProduct(string productType) ]
  [InvestmentFactory] <:-- [PublicSectorFactory |  GetProduct(string productType) ]
  [<interface>IInvestment] <- [SBI]
  [<interface>IInvestment] <- [ICICI]
  [<interface>IInvestment] <- [GovtFund]
  [<interface>IInvestment] <- [RelianceFund]
  [PublicSectorFactory]-->[SBI]
  [PublicSectorFactory]-->[GovtFund]
  [PublicSectorFactory]-->[ICICI]
  [PublicSectorFactory]-->[RelianceFund]
]

Solutions

client

    #region Abstract Factory design pattern

    ConsoleColorMethod("Abstract Factory design pattern");

    var investmentPrivateFactory = InvestmentFactory.CreateFactory("Private");
    string productType = investmentPrivateFactory.GetProduct("ICICI").FD(1000);

    Console.WriteLine(productType);

    Console.WriteLine(InvestmentFactory.CreateFactory("Public").GetProduct("SBI").MF(50000));
    #endregion

namespace AbstractFactoryDesignPattern
{
    // Creating Abstract product
    public interface Investment
    {
        string FD(double amount);
        string MF(double amount);
    }

    // Creating Concrete Product
    public class SBI : Investment
    {
        public string FD(double amount)
        {
            return "Fix Deposit of INR " + amount + " is done in SBI";
        }

        public string MF(double amount)
        {
            return "Mutual fund of INR " + amount + " is done in SBI";
        }
    }

    // Creating Concrete Product
    public class ICICI : Investment
    {
        public string FD(double amount)
        {
            return "Fix Deposit of INR " + amount + " is done in ICICI";
        }

        public string MF(double amount)
        {
            return "Mutual fund of INR " + amount + " is done in ICICI";
        }
    }

    public class GovtFund : Investment
    {
        public string FD(double amount)
        {
            return "Fix Deposit of INR " + amount + " is done in GovtFund";
        }

        public string MF(double amount)
        {
            return "Mutual fund of INR " + amount + " is done in GovtFund";
        }
    }

    public class RelianceFund : Investment
    {
        public string FD(double amount)
        {
            return "Fix Deposit of INR " + amount + " is done in RelianceFund";
        }

        public string MF(double amount)
        {
            return "Mutual fund of INR " + amount + " is done in RelianceFund";
        }
    }



    //Creating the Abstract Factory
    public abstract class InvestmentFactory
    {
        public abstract Investment GetProduct(string InvestType);
        public static InvestmentFactory CreateFactory(string InvestType)
        {
            if (InvestType.Equals("Private"))
                return new PrivateSectorFactory();
            else
                return new PublicSectorFactory();
        }
    }


    //Creating Concrete Factory
    public class PrivateSectorFactory : InvestmentFactory
    {
        public override Investment GetProduct(string productType)
        {
            if (productType.Equals("ICICI"))
            {
                return new ICICI();
            }
            else if (productType.Equals("RelianceFund"))
            {
                return new RelianceFund();
            }
            else
                return null;
        }
    }

    public class PublicSectorFactory : InvestmentFactory
    {
        public override Investment GetProduct(string productType)
        {
            if (productType.Equals("SBI"))
            {
                return new SBI();
            }
            else if (productType.Equals("RelianceFund"))
            {
                return new GovtFund();
            }
            else
                return null;
        }
    }
}