自己动手写计算器v1.2

　　1.2版本主要添加了分数、取负、开方三个功能，由于这三中运算输入单目运算，所以，新声明了一个新类

　　class OPeratorV1_2

至此基本完成了一个标准计算器，至于拥有更多功能的科学计算器，日后再做开发，暂定版本2.0

代码如下：

自己写的操作类，负责各种运算，由于是利用了工厂模式，以后新增功能会很方便，特别是今天添加上面的三个功能时，深深体会到了模式的好处。

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

namespace 计算器
{
    //简述：用工厂模式取代了简单工厂模式，对比与简单工厂模式，工厂模式，将简单工厂类中的逻辑判断利用接口分离了开来。
    interface Result
    {
        OperatorV1_1 getOperatorV1_1();
    }
    class plusOperatorV1_1Factory:Result
    {
        public OperatorV1_1 getOperatorV1_1()
        {
            return new plusOperatorV1_1();
        }
    }
    class jianOperatorV1_1Factory:Result
    {
        public OperatorV1_1 getOperatorV1_1()
        {
            return new jianOperatorV1_1();
        }
    }
    class chenOperatorV1_1Factory:Result
    {
        public OperatorV1_1 getOperatorV1_1()
        {
            return new chenOperatorV1_1();
        }
    }
    class chuOperatorV1_1Factory:Result
    {
        public OperatorV1_1 getOperatorV1_1()
        {
            return new chenOperatorV1_1();
        }
    }
    class OperatorV1_1
    {
        public virtual string GetResult(double num1, double num2)
        {
            return "error";
        }
    }
    //负责开方、分数、取负
    class OPeratorV1_2
    {
        public virtual string GetResult(double num)
        {
            return "error";
        }
    }
    //开方
    class kaiFangOperatorV1_2:OPeratorV1_2
    {
        public override string GetResult(double num)
        {    
                num = Math.Sqrt(num);
                return num.ToString(); 
        }
    }
    //分数
    class fenShuOperatorV1_2 : OPeratorV1_2
    {
        public override string GetResult(double num)
        {
            num = 1 / num;
            return num.ToString();
        }
    } 
    //取负
    class quFuOperatorV1_2:OPeratorV1_2
    {
        public override string GetResult(double num)
        {
            num = -num;
            return num.ToString();
        }
    }
    class plusOperatorV1_1 : OperatorV1_1
    {
        public override string GetResult(double num1, double num2)
        {
            return (num1 + num2).ToString();
        }
    }
    class jianOperatorV1_1 : OperatorV1_1
    {
        public override string GetResult(double num1, double num2)
        {
            return (num1 - num2).ToString();
        }
    }
    class chenOperatorV1_1 : OperatorV1_1
    {
        public override string GetResult(double num1, double num2)
        {
            return (num1 * num2).ToString();
        }
    }
    class chuOperatorV1_1 : OperatorV1_1
    {
        public override string GetResult(double num1, double num2)
        {
            if (num2 == 0)
            {
                return "除数不能为0";
            }
            else
            {
                return (num1 / num2).ToString();
            }
        }
    }
}

后台控件代码：

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

namespace 计算器
{
    //public class Check
    //{
    //    public void CheckTextbox(string num)
    //    {
    //        StringBuilder str = new StringBuilder();
    //        if (this.textBox1.Text != "")
    //        {
    //            str.Append(this.textBox1.Text);
    //            str.Append(num);
    //            this.textBox1.Text = str.ToString();
    //        }
    //        else
    //        {
    //            this.textBox1.Text = num;
    //        }
    //    }
    //    public void CheckYunSuan(string myOperator)
    //    {
    //        StringBuilder str = new StringBuilder();
    //        if (this.textBox1.Text != "")
    //        {
    //            str.Append(this.textBox1.Text);
    //            str.Append(myOperator);
    //            this.textBox1.Text = str.ToString();
    //        }
    //        else
    //        {
    //            this.textBox1.Text = myOperator;
    //        }
    //    }
    //}
    public partial class Form1 : Form
    {
        //简述：变量集中声明处
        StringBuilder num1 = new StringBuilder();
        StringBuilder num2 = new StringBuilder();
        public void CheckTextbox(string num)
        {
            StringBuilder str = new StringBuilder();
            if (this.textBox1.Text != "" && this.textBox1.Text != "非数字" && this.textBox1.Text != "参数错误")//当为负数开方时，会报错“非数字”。当连续点击运算符时，会导致运算参数不完整，会报“参数错误”
            {
                str.Append(this.textBox1.Text);
                str.Append(num);
                this.textBox1.Text = str.ToString();
            }
            else
            {
                this.textBox1.Text = num;
            }
        }
        //简述：输入运算符。 2016-5-13 张杨
        public void CheckYunSuan(string myOperator)
        {
            StringBuilder str = new StringBuilder();
            string sText = this.textBox1.Text;
            if (this.textBox1.Text != "")
            {
                string s = this.textBox1.Text;
                if (textBox1.Text.Contains("+") || s[0] != '-' && textBox1.Text.Contains("-") || textBox1.Text.Contains("*") || textBox1.Text.Contains("/"))
                {
                    ShowResult();
                }
                else if (myOperator == "Q" || myOperator == "F" || myOperator == "K")
                {
                    ShowResult(myOperator);
                }
                str.Append(this.textBox1.Text);
                //后面的两个判断主要是因为如果出现错误的话，就要避免此种情况下在错误信息上添加运算符的情况。
                if (myOperator != "Q" && myOperator != "F" && myOperator != "K"&&!this.textBox1.Text.Contains("参数错误")&&!this.textBox1.Text.Contains("非数字"))
                {
                    str.Append(myOperator);
                }
                if(sText==str.ToString())//判定是否执行过相关运算
                {
                    this.textBox1.Text = "参数错误";
                }
                else
                {
                    this.textBox1.Text = str.ToString();
                }
               
            }
            else
            {
                this.textBox1.Text = myOperator;
            }
        }

        public Form1()
        {
            InitializeComponent();
        }
        //简述：判断是否是计算完毕后的再次点击。  2016-5-13 张杨
        //修改：废除。 2016-5-13 张杨
        //private void textboxIsNull()
        //{
        //    if (this.textBox1.Text.Contains("结果为"))
        //    {
        //        this.textBox1.Text = "";
        //    }
        //}
        #region 数字类
        private void button1_Click(object sender, EventArgs e)
        {
            CheckTextbox("1");
        }

        private void button2_Click(object sender, EventArgs e)
        {
            CheckTextbox("2");
        }

        private void button3_Click(object sender, EventArgs e)
        {
            CheckTextbox("3");
        }

        private void button4_Click(object sender, EventArgs e)
        {
            CheckTextbox("4");
        }

        private void button5_Click(object sender, EventArgs e)
        {
            CheckTextbox("5");
        }

        private void button6_Click(object sender, EventArgs e)
        {
            CheckTextbox("6");
        }

        private void button7_Click(object sender, EventArgs e)
        {
            CheckTextbox("7");
        }

        private void button8_Click(object sender, EventArgs e)
        {
            CheckTextbox("8");
        }

        private void button9_Click(object sender, EventArgs e)
        {
            CheckTextbox("9");
        }
        #endregion
        #region 加减乘除运算
        //简述：下面的为加减乘除功能。
        //2016-5-13 张杨

        private void button10_Click(object sender, EventArgs e)
        {
            CheckYunSuan("+");
        }

        private void button11_Click(object sender, EventArgs e)
        {
            CheckYunSuan("-");
        }

        private void button12_Click(object sender, EventArgs e)
        {
            CheckYunSuan("*");
        }

        private void button13_Click(object sender, EventArgs e)
        {
            CheckYunSuan("/");
        }
        #endregion
        private void button14_Click(object sender, EventArgs e)
        {
            this.textBox1.Text = String.Empty;
        }
        //简述：判断字符是否为运算符。 2016-5-13  张杨
        public bool isOperator(char key)
        {
            if (key == '+' || key == '-' || key == '*' || key == '/')
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        //简述：计算结果。  2016-5-13    张杨
        private void ShowResult(string Operator = "")
        {
            string strText = this.textBox1.Text;
            char myOperator = 'A';
            if (Operator != "")
            {
                myOperator = Operator[0];
            }
            int flag = 0;
            string result = "";
            OperatorV1_1 newResult = new OperatorV1_1();
            //取负、分数、开方的运算对象
            OPeratorV1_2 newResult2 = new OPeratorV1_2();
            if (strText[0] == '-')//针对为多位负数开方的情况。
            {
                num1.Append('-');
            }
            foreach (char key in strText)
            {
                if (strText[0] == key && key == '-')
                {
                    continue;
                }
                if (isOperator(key))
                {
                    flag = 1;
                    myOperator = key;
                    continue;
                }
                else
                {

                    switch (flag)
                    {
                        case 0:

                            num1.Append(key);

                            break;
                        case 1: num2.Append(key); break;
                    }
                }
            }
            switch (myOperator)
            {
                case '+': newResult = new plusOperatorV1_1(); break;
                case '-': newResult = new jianOperatorV1_1(); break;
                case '*': newResult = new chenOperatorV1_1(); break;
                case '/': newResult = new chuOperatorV1_1(); break;
                case 'Q': newResult2 = new quFuOperatorV1_2(); break;
                case 'K': newResult2 = new kaiFangOperatorV1_2(); break;
                case 'F': newResult2 = new fenShuOperatorV1_2(); break;
            }
            if (myOperator == 'Q' || myOperator == 'K' || myOperator == 'F')
            {
                if (num1.ToString() != null)
                {
                    result = newResult2.GetResult(double.Parse(num1.ToString()));
                }
                else
                {
                    result = "参数错误";
                }
            }
            else
            {
                string s1 = num1.ToString();
                string s2 = num2.ToString();
                if (s1.Length>0&& s2.Length>0)
                {
                    if (!isOperator(s1[0]) && !isOperator(s2[0]))
                        result = newResult.GetResult(double.Parse(num1.ToString()), double.Parse(num2.ToString()));
                }
                else
                {
                    result = "参数错误";
                }

            }
            //result = OperatorFactory.GetResult(myOperator, double.Parse(num1.ToString()), double.Parse(num2.ToString()));
            num1 = num1.Remove(0, num1.Length);
            num2 = num2.Remove(0, num2.Length);
            this.textBox1.Text = result;
        }
        private void button15_Click(object sender, EventArgs e)
        {
            ShowResult();
        }
        #region 取负，分数，开方
        //开方
        private void button16_Click(object sender, EventArgs e)
        {
            string s = this.textBox1.Text;
            if (textBox1.Text.Contains("+") || s[0] != '-' && textBox1.Text.Contains("-") || textBox1.Text.Contains("*") || textBox1.Text.Contains("/"))
            {
                ShowResult();
            }
            CheckYunSuan("K");
        }
        //分数
        private void button17_Click(object sender, EventArgs e)
        {
            string s = this.textBox1.Text;
            if (textBox1.Text.Contains("+") || s[0] != '-' && textBox1.Text.Contains("-") || textBox1.Text.Contains("*") || textBox1.Text.Contains("/"))
            {
                ShowResult();
            }
            CheckYunSuan("F");
        }
        //取负
        private void button18_Click(object sender, EventArgs e)
        {
            string s = this.textBox1.Text;
            if (textBox1.Text.Contains("+") || s[0] != '-' && textBox1.Text.Contains("-") || textBox1.Text.Contains("*") || textBox1.Text.Contains("/"))
            {
                ShowResult();
            }
            CheckYunSuan("Q");
        }
        #endregion
    }
}

控件设计形式：