C#简单工厂模式实现松耦合度四则运算

  1 using System;
  2 public class Operation
  3 {
  4     private double _numberA = 0;
  5     private double _numberB = 0;
  6     
  7     public double NumberA
  8     {
  9         get { return _numberA; }
 10         set { _numberA = value; }
 11     }
 12     public double NumberB
 13     {
 14         get { return _numberB; }
 15         set { _numberB = value; }
 16     }
 17     public virtual double GetResult()
 18     {
 19         double result = 0;
 20         return result;
 21     }
 22 }
 23 
 24 class OperationAdd : Operation
 25 {
 26     public override double GetResult()
 27     {
 28         double result = 0;
 29         result = NumberA + NumberB;
 30         return result;
 31     }
 32 }
 33 
 34 class OperationSub : Operation
 35 {
 36     public override double GetResult()
 37     {
 38         double result = 0;
 39         result = NumberA - NumberB;
 40         return result;
 41     }
 42 }
 43 
 44 class OperationMul : Operation
 45 {
 46     public override double GetResult()
 47     {
 48         double result = 0;
 49         result = NumberA * NumberB;
 50         return result;
 51     }
 52 }
 53 
 54 class OperationDiv : Operation
 55 {
 56     public override double GetResult()
 57     {
 58         double result = 0;
 59         if (NumberB == 0)
 60             throw new Exception("div number can not be 0.");
 61         result = NumberA / NumberB;
 62         return result;
 63     }
 64 }
 65 
 66 public class OperationFactory
 67 {
 68     public static Operation createOperate(string operate)
 69     {
 70         Operation oper = null;
 71         switch (operate)
 72         {
 73             case "+":
 74                 oper = new OperationAdd();
 75                 break;
 76             case "-":
 77                 oper = new OperationSub();
 78                 break;
 79             case "*":
 80                 oper = new OperationMul();
 81                 break;
 82             case "/":
 83                 oper = new OperationDiv();
 84                 break;
 85         }
 86         return oper;
 87     }
 88 }
 89 public class OperationClient
 90 {
 91     class Program
 92     {
 93         public static void Main(string[] args)
 94         {
 95             Operation oper;
 96 
 97             Console.Write("Please input numberA: ");
 98             string strNumberA = Console.ReadLine();
 99             Console.Write("Please select operate(+ - * /): ");
100             string strOperate = Console.ReadLine();
101             oper = OperationFactory.createOperate(strOperate);
102             Console.Write("Please input numberB: ");
103             string strNumberB = Console.ReadLine();
104             oper.NumberA = Convert.ToDouble(strNumberA);
105             oper.NumberB = Convert.ToDouble(strNumberB);
106             string strResult = "";
107             strResult = Convert.ToString(oper.GetResult());
108             Console.WriteLine("Result is :" + strResult);
109             Console.ReadLine();
110             Console.Write("Press any key to continue . . . ");
111             Console.ReadKey(true);
112         }
113     }
114 }