class1.cs

C#开发教程 由浅入深 配有实例 是初学者的好帮手

using System;

namespace NewVirtuals
{
	class Employee
	{
		public string name;

//		virtual public Employee(string name)	// illegal
		public Employee(string name)
		{
			this.name = name;
		}

		public virtual void CalculatePay()
		{
			Console.WriteLine(
				"Employee.CalculatePay called for {0}", 
				name);
		}
	}

	class SalariedEmployee : Employee
	{
		public SalariedEmployee (string name) : base(name)
		{
		}

		// these are the same
		public new virtual void CalculatePay()
//		public virtual void CalculatePay()
		{
			Console.WriteLine(
				"SalariedEmployee.CalculatePay called for {0}", 
				name);
		}
	}

	class ContractEmployee : SalariedEmployee
	{
		public ContractEmployee(string name) : base(name)
		{
		}

		public override void CalculatePay()
		{
			Console.WriteLine(
				"ContractEmployee.CalculatePay called for {0}", 
				name);
		}
	}

	class TestNewVirtuals
	{
		protected Employee[] employees;

		public void LoadEmployees()
		{
			employees = new Employee[2];
			employees[0] = new ContractEmployee(
				"Adam Barr");
			employees[1] = new SalariedEmployee(
				"Max Benson");
		}

		public void ProcessSalariedEmployees()
		{
			SalariedEmployee[] se = new SalariedEmployee[2];
			se[0] = new ContractEmployee("Adam Barr");
			se[1] = new SalariedEmployee("Max Benson");
			for (int i = 0; i < se.GetLength(0); i++)
			{
				se[i].CalculatePay();
			}
		}

		public void DoPayroll()
		{
			for (int i = 0; i < employees.GetLength(0); i++)
			{
				employees[i].CalculatePay();
			}
		}

		[STAThread]
		static void Main(string[] args)
		{
			TestNewVirtuals t = new TestNewVirtuals();
			t.LoadEmployees();
			t.DoPayroll();

			Console.WriteLine();
			t.ProcessSalariedEmployees();
		}
	}
}