Design patterns may be said as a set of probable solutions for a particular problem which is tested to work best in certain situations.
These patterns deals mainly with creation of objects and classes.
Factory method design pattern abstract the process of object creation and allows the object to be created at run-time when it is required.
using System;
namespace FactoryPatternDemo
{
// 'IProduct' Interface
interface IFactory {
void details();
}
// 'ConcreteProduct' class
class PermanentEmployee : IFactory
{
public void details()
{
Console.WriteLine("This is permanent employee type object");
}
}
// 'ConcreteProduct' class
class TemporaryEmployee : IFactory
{
public void details()
{
Console.WriteLine("This is Temporary employee type object");
}
}
// 'Creator' abstract class
abstract class EmployeeFactory
{
public abstract IFactory Factory(string employeeType);
}
// 'ConcrteCreator' class
class ConcreteEmployeeFactory : EmployeeFactory
{
public override IFactory Factory(string employeeType)
{
switch (employeeType)
{
case "PermanentEmployee":
return new PermanentEmployee();
case "TemporaryEmployee":
return new TemporaryEmployee();
default:
throw new ApplicationException(string.Format("This type of employee can not be created"));
}
}
}
// factory method design pattern demo
// calling class/ client
class Program
{
static void Main(string[] args)
{
EmployeeFactory EmployeeFactory = new ConcreteEmployeeFactory();
IFactory permanentEmployee = EmployeeFactory.Factory("PermanentEmployee");
permanentEmployee.details();
IFactory TemporaryEmployee = EmployeeFactory.Factory("TemporaryEmployee");
TemporaryEmployee.details();
Console.ReadLine();
}
}
}These patterns deals with Class and Object Composition.
These mainly deals with Class - Object communication.