Calculation

定义一个Strategy接口，其中定义一个方法，用于计算

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Calculation
{
    interface Interface1
    {
        int calculate(int a, int b);
    }
}

 定义具体的算法类，实现Strategy接口，算法类中的算法各自不同：加减乘等

1，加法类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Calculation
{
    class Add:Interface1
    {
        public int calculate(int a, int b)
        {   
            return  a + b;
        }
    
    }
}

 2，减法类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Calculation
{
    class Subtract : Interface1
    {
        public int calculate(int a, int b)
        {
            return  a - b;
        }
    }
}

 3，乘法类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Calculation
{
    class Multiply:Interface1
    {
        public int calculate(int a, int b)
        {
         
             return a * b;
        }

    }
}

 4，除法类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Calculation
{
    class Except:Interface1
    {
        public int calculate(int a, int b)
        {     
            return  a / b ;

        }
    }
}

 定义具体的环境角色

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Calculation
{
    class Environment
    {
        private Interface1 inter;
        public Environment(Interface1 face)
        {
            inter = face;
        }
        public Interface1 gewrt()
        {
            return inter;
        }
        public void setwrt(Interface1 face)
        {
            inter=face;
        }
        public int calculate(int a, int b)
        {
            return inter.calculate(a, b);
        }

    }
}

 form1的代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace Calculation
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            displays();
        }
        private void displays()
        {
            Random random = new Random();
            int a, b;
            a = random.Next(0, 100);
            b = random.Next(0, 100);
            fasttext.Text = a.ToString();
            lasttext.Text = b.ToString();
            string[] operjact = new string[] { "+", "-", "*", "/" };
            string f = operjact[new Random().Next(0, 4)];
            operja.Text = f;
 
        }

        private void textBox3_KeyDown(object sender, KeyEventArgs e)
        {
            int a = int.Parse(fasttext.Text);
            int b = int.Parse(lasttext.Text);
            
            if (e.KeyCode == Keys.Enter)
            {

                int answer = int.Parse(textBox3.Text);
               
                string OPter=operja.Text;
                switch (OPter)
                {
                    case "+":
                        Add addss = new Add();
                        Environment environment = new Environment(addss);
                        environment.calculate(a, b);
                        if (answer == environment.calculate(a, b))
                        {
                            MessageBox.Show("回答正确！");
                        }
                        else
                        {
                            MessageBox.Show("回答错误！");
                        }
                        break;
                    case "-":
                         Subtract subtrss = new Subtract();
                         Environment environment1 = new Environment(subtrss);
                         environment1.calculate(a,b);
                         if (answer == environment1.calculate(a, b))
                         {
                             MessageBox.Show("回答正确！");
                         }
                         else
                         {
                             MessageBox.Show("回答错误！");
                         }
                       break;
                    case "*":
                       Multiply muli = new Multiply();
                       Environment environment2 = new Environment(muli);
                       environment2.calculate(a, b);
                       if (answer == environment2.calculate(a, b))
                       {
                           MessageBox.Show("回答正确！");
                       }
                       else
                       {
                           MessageBox.Show("回答错误！");
                       }
                       break;
                    case "/":
                       Except except = new Except();
                       Environment enviroment3 = new Environment(except);
                       enviroment3.calculate(a, b);
                        if(answer==enviroment3.calculate(a,b))
                        {
                            MessageBox.Show("回答正确！");
                        }
                        else
                        {
                            MessageBox.Show("回答错误！");
                        }
                       break;
                       

                }
                textBox3.Clear();
                displays();
                
             
                  
                  
                
            }

        }
    }
}

 总结：

两个数是让它随机产生的，运算符是随机产生的，无法保证除以零的情况。总的来说这些代码套来套去的有点发晕。不知道自己写的怎么样。 

其中有一部分代码不太明白感觉没什么用？

   public Interface1 gewrt()
        {
            return inter;
        }
        public void setwrt(Interface1 face)
        {
            inter=face;
        }

就把他们删了试着运行了一下，还是可以正常运行。