浅浅一谈设计模式

看软件设计资料，走到设计模式这里，一头雾水。遂翻书学习，这里简单记录一下，为以后复习用

1，简单工厂

简单工厂写一个计算加减乘除的运算

 1  class Program
 2     {
 3         static void Main(string[] args)
 4         {
 5             SampleFactory factory = new SampleFactory();
 6             OperationClass operationclass = factory.CreateOpreation('/');
 7             //找到要操作的类了
 8             //对类进行初始化
 9             operationclass.FirstNum = 1;
10             operationclass.SecondeNum = 3;
11 
12             //调用函数 进行计算
13          double result=   operationclass.GetResult();
14            
15            Console.Write(result.ToString());
16            Console.Read();
17         }
18     }
19 
20     /// <summary>
21     /// 运算类
22     /// </summary>
23     class OperationClass
24     {
25         private double firstNum;
26 
27         public double FirstNum
28         {
29             get { return firstNum; }
30             set { firstNum = value; }
31         }
32         private double secondeNum;
33 
34         public double SecondeNum
35         {
36             get { return secondeNum; }
37             set { secondeNum = value; }
38         }
39 
40         private double result;
41         public virtual double GetResult()
42         {
43             result = 0;
44             return result;
45         }
46 
47     }
48 
49 
50     class Add :OperationClass
51     {
52         public override double GetResult()
53         {
54             return FirstNum + SecondeNum;
55         }
56     }
57 
58     class Sub : OperationClass
59     {
60         public override double GetResult()
61         {
62             return FirstNum - SecondeNum;
63         }
64     }
65 
66     class Chu : OperationClass
67     {
68         public override double GetResult()
69         {
70             return FirstNum / SecondeNum;
71         }
72     }
73     /// <summary>
74     /// 简单工厂
75     /// </summary>
76     class SampleFactory
77     {
78         public OperationClass CreateOpreation(char c)
79         {
80             OperationClass operationclass;//运算类  基类
81             switch (c)
82             {
83                 case '+':
84                     operationclass = new Add();
85                     break;
86                     case '-':
87                     operationclass=new Sub();
88                     break;
89                     case '/':
90                     operationclass = new Chu    ();
91                     break;
92                 default:
93                     operationclass =null;
94                     break;
95             }
96             return operationclass;
97         }
98     }

View Code

在功能变动时

优点：客户端不用改代码

缺点：当需要增加新的运算类的时候，不仅需新加运算类，还要修改工厂类，违反了开闭原则。

2.工厂方法模式

浅浅一谈 设计模式

浅浅一谈设计模式