Abstract Factory Pattern

ABSTRACT FACTORY PATTERN

          Provide an interface for creating families of related or dependent objects without specifying their
concrete classes.


                         Casual Implementation                             Factory Pattern Implementation

Usual Code Block

Factory Pattern

Parent Class public class CheckBook {     protected decimal _Amount;     public decimal getExpense()     {       return _Amount;     } } These below child classes is derived from CheckBook base class. public class Health : CheckBook {     public Health()     {         _Amount = 5000;//Could be any logic to calculate health amount         Console.WriteLine("Your Health Expense: {0}", _Amount.ToString());     } } public class Travel : CheckBook {     public Travel()     {         _Amount = 10000;//Could be any logic to calculate travel amount         Console.WriteLine("Your Travel Expense: {0}", _Amount.ToString());     } } public class Personal : CheckBook {     public Personal()     {         _Amount = 15000;//Could be any logic to calculate personal amount         Console.WriteLine("Your Personal Expense: {0}", _Amount.ToString());     } }

public class CheckFactory {     public CheckFactory() { }     public CheckBook chooseExpense(int o)     {         switch (o)         {             case 1:                 return new Personal();             case 2:                 return new Travel();             default:                 return new Health();         }     } } class Program {     static void Main(string[] args)     {         string input = Console.ReadLine();         CheckFactory objCheckFactory = new CheckFactory();         CheckBook currentExpense = objCheckFactory.chooseExpense(int.Parse(input));         Console.WriteLine("From main class " + currentExpense.getExpense());         Console.Read();     } }