简单计算器

编写工具：c#

主要cs文件

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 calculator
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        
        int numberxiabiao_int = 0;//数字集合下标
        int operatorxiabiao_int = 0;//运算符下标
        double[] number_double = new double[10];//数字集合
        string[] operator_string = new string[10];//运算符集合

        public void numclik(int num)
        {//输入数字
                if (textBox1.Text == "0")
                {
                    //输入的是整数第一个数字
                    textBox1.Text = num + "";
                }
                else
                {
                    //输入的不是整数的第一个数字
                    textBox1.Text = textBox1.Text+ num + "";
                }
        }
        private void button3_Click(object sender, EventArgs e)
        {
            //按钮 1
            numclik(1);
        }

        private void button6_Click(object sender, EventArgs e)
        {
            //按钮 2
            numclik(2);
        }

        private void button9_Click(object sender, EventArgs e)
        {
            //按钮 3
            numclik(3);
        }

        private void button2_Click(object sender, EventArgs e)
        {
            //按钮 4
            numclik(4);
        }

        private void button5_Click(object sender, EventArgs e)
        {
            //按钮 5
            numclik(5);
        }

        private void button8_Click(object sender, EventArgs e)
        {
            //按钮 6
            numclik(6);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            //按钮 7
            numclik(7);
        }

        private void button4_Click(object sender, EventArgs e)
        {
            //按钮 8
            numclik(8);
        }

        private void button7_Click(object sender, EventArgs e)
        {
            //按钮 9
            numclik(9);
        }

        private void button10_Click(object sender, EventArgs e)
        {
            //按钮 0
            numclik(0);
        }

        private void button11_Click(object sender, EventArgs e)
        {
            //按钮 点
            string a = textBox1.Text;
            if (a.Length > 1)//如果长度大于1进行判断，这判断出现的原因是为了不让下边截取字符串部分下标不少于0
            {
                string b = a.Substring(a.Length - 1);
                string c = "+";
                string d = "-";
                string h = "*";
                string f = "/";
                string g = ".";
                if (b != c && b != d && b != h && b != f && b != g)//不能连续输入运算符或者小数点
                {
                    textBox1.Text = textBox1.Text + ".";
                }
            }
            else
            {
                if (textBox1.Text != "")
                {
                    textBox1.Text = textBox1.Text + ".";
                }
            }
        }

        private void button12_Click(object sender, EventArgs e)
        {
            //按钮 +
            string a = textBox1.Text;
            if (a.Length > 1)//如果长度大于1进行判断，这判断出现的原因是为了不让下边截取字符串部分下标不少于0
            {
                string b = a.Substring(a.Length - 1);
                string c = "+";
                string d = "-";
                string h = "*";
                string f = "/";
                string g = ".";
                if (b != c && b != d && b != h && b != f && b != g)//不能连续输入运算符或者小数点
                {
                    textBox1.Text = textBox1.Text + "+";
                }
            }
            else
            {
                if (textBox1.Text != "")
                {
                    textBox1.Text = textBox1.Text + "+";
                }
            }
        }

        private void button13_Click(object sender, EventArgs e)
        {
            //按钮 -
            string a = textBox1.Text;
            if (a.Length > 1)//如果长度大于3进行判断，这判断出现的原因是为了不让下边截取字符串部分下标不少于0
            {
                string b = a.Substring(a.Length - 1);
                string c = "+";
                string d = "-";
                string h = "*";
                string f = "/";
                string g = ".";
                if (b != c && b != d && b != h && b != f && b != g)//不能连续输入乘号或者
                {
                    textBox1.Text = textBox1.Text + "-";
                }
            }
            else
            {
                if (textBox1.Text != "")
                {
                    textBox1.Text = textBox1.Text + "-";
                }
            }
        }

        private void button14_Click(object sender, EventArgs e)
        {
            //按钮 *
            string a = textBox1.Text;
            if (a.Length > 1)//如果长度大于3进行判断，这判断出现的原因是为了不让下边截取字符串部分下标不少于0
            {
                string b = a.Substring(a.Length - 1);
                string c = "+";
                string d = "-";
                string h = "*";
                string f = "/";
                string g = ".";
                if (b != c && b != d && b != h && b != f && b != g)//不能连续输入乘号或者
                {
                    textBox1.Text = textBox1.Text + "*";
                }
            }
            else
            {
                if (textBox1.Text != "")
                {
                    textBox1.Text = textBox1.Text + "*";
                }
            }
        }

        private void button15_Click(object sender, EventArgs e)
        {
            //按钮 /
            string a = textBox1.Text;
            if (a.Length > 1)//如果长度大于3进行判断，这判断出现的原因是为了不让下边截取字符串部分下标不少于0
            {
                string b = a.Substring(a.Length - 1);
                string c = "+";
                string d = "-";
                string h = "*";
                string f = "/";
                string g = ".";
                if (b != c && b != d && b != h && b != f && b != g)//不能连续输入乘号或者
                {
                    textBox1.Text = textBox1.Text + "/";
                }
            }
            else
            {
                if (textBox1.Text != "")
                {
                    textBox1.Text = textBox1.Text + "/";
                }
            }
        }

        private void button16_Click(object sender, EventArgs e)
        {
            //按钮 清除一位
            if (textBox1.Text != "")
            {
                textBox1.Text = textBox1.Text.Substring(0, textBox1.Text.Length - 1);
            }
        }

        private void button17_Click(object sender, EventArgs e)
        {
            //按钮 清除所有内容重新开始
            textBox1.Text = "0";//显示为零
            numberxiabiao_int = 0;
            operatorxiabiao_int = 0;//两个记录数组都清空,清空的方式就是把数组的下标重置，而不是重置数组，严格来说也不能
        }

        private void button18_Click(object sender, EventArgs e)
        {
            //按钮 =
            string a = textBox1.Text;
            int i = 0;//定义一个总的字符串下标
            while (a != "" && i < a.Length)//将字符串分为数字还有符号
            {
                string b = "";
                while (!a[i].Equals('+') && !a[i].Equals('-') && !a[i].Equals('*') && !a[i].Equals('/') && i < a.Length)//这个循环的出现是为了过滤多位数字，还有小数
                {   //一直把向后叠加，直到后面一位是运算符，这样才能完全统计这个数字
                    b = b + a[i];
                    i++; 
                    if (i < a.Length)
                    {
                        if (a[i].Equals('+') || a[i].Equals('-') || a[i].Equals('*') || a[i].Equals('/'))//如果下一个字符是运算符，就存储数字
                        {
                            number_double[numberxiabiao_int] = Convert.ToDouble(b);
                            numberxiabiao_int++;
                            break;
                        }
                    }
                    else
                    {
                        number_double[numberxiabiao_int] = Convert.ToDouble(b);
                        numberxiabiao_int++;
                        break;
                    }
                }

                if (i == a.Length)
                {
                    break; 
                }
                else
                {
                    operator_string[operatorxiabiao_int] = a[i] + "";
                    i++;
                    operatorxiabiao_int++;
                }
            }
            if (numberxiabiao_int == 2)//有两个数字的情况
            {
                if (operator_string[operatorxiabiao_int-1] == "+")
                {
                    double result = number_double[0] + number_double[1];
                    numberxiabiao_int = 0;
                    operatorxiabiao_int = 0;
                    textBox1.Text = result + "";
                }
                else if (operator_string[operatorxiabiao_int-1] == "-")
                {
                    double result = number_double[0] - number_double[1];
                    numberxiabiao_int = 0;
                    operatorxiabiao_int = 0;
                    textBox1.Text = result + "";
                }
                else if (operator_string[operatorxiabiao_int-1] == "*")
                {
                    double result = number_double[0] * number_double[1];
                    numberxiabiao_int = 0;
                    operatorxiabiao_int = 0;
                    textBox1.Text = result + "";
                }
                else if (operator_string[operatorxiabiao_int-1] == "/")
                {
                    double result = number_double[0] / number_double[1];
                    numberxiabiao_int = 0;
                    operatorxiabiao_int = 0;
                    textBox1.Text = result + "";
                }
            }
            else if (numberxiabiao_int == 3)//有三个数字的情况
            {
                string operator1 = operator_string[0];
                string operator2 = operator_string[1];
                if (operator1 == "+")
                {
                    if (operator2 == "+")
                    {
                        double result = number_double[0] + number_double[1] + number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "-")
                    {
                        double result = number_double[0] + number_double[1] - number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "*")
                    {
                        double result = number_double[0] + number_double[1] * number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "/")
                    {
                        double result = number_double[0] + number_double[1] / number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                }
                else if (operator1 == "-")
                {
                    if (operator2 == "+")
                    {
                        double result = number_double[0] - number_double[1] + number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "-")
                    {
                        double result = number_double[0] - number_double[1] - number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "*")
                    {
                        double result = number_double[0] - number_double[1] * number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "/")
                    {
                        double result = number_double[0] - number_double[1] / number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                }
                else if (operator1 == "*")
                {
                    if (operator2 == "+")
                    {
                        double result = number_double[0] * number_double[1] + number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "-")
                    {
                        double result = number_double[0] * number_double[1] - number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "*")
                    {
                        double result = number_double[0] * number_double[1] * number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "/")
                    {
                        double result = number_double[0] * number_double[1] / number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                }
                else if (operator1 == "/")
                {
                    if (operator2 == "+")
                    {
                        double result = number_double[0] / number_double[1] + number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "-")
                    {
                        double result = number_double[0] / number_double[1] - number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "*")
                    {
                        double result = number_double[0] / number_double[1] * number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                    else if (operator2 == "/")
                    {
                        double result = number_double[0] / number_double[1] / number_double[2];
                        numberxiabiao_int = 0;
                        operatorxiabiao_int = 0;
                        textBox1.Text = result + "";
                    }
                }
            }
            numberxiabiao_int = 0;
            operatorxiabiao_int = 0;//两个记录数组都清空
        }

        private void button19_Click(object sender, EventArgs e)
        {
            //按钮 开根号
            string b = textBox1.Text;//一个简单的承接，把显示的字符串
            string c = "";
            string c2 = "";
            double c1 = 0;
            int n = 0;
            bool flag = true;//用来判断是不是只有一个数字
            for (int j = 0; j < b.Length; j++)
            {
                if (b[j].Equals('+') || b[j].Equals('-') || b[j].Equals('*') || b[j].Equals('/'))
                {
                    flag = false;
                    break;
                }
            }
            if (flag == false)
            {
                if (!b[b.Length - 1].Equals('+') && !b[b.Length - 1].Equals('-') && !b[b.Length - 1].Equals('*') && !b[b.Length - 1].Equals('/'))//只能是最后一个字符为数字是才能执行
                {
                    for (int k = b.Length - 1; k > -1; k--)
                    {
                        if (b[k].Equals('+') || b[k].Equals('-') || b[k].Equals('*') || b[k].Equals('/'))
                        {
                            n = k;
                            break;
                        }
                    }
                }
                for (int g = n; g < b.Length; g++)
                {
                    c += b[g];
                }
                c1 = Convert.ToDouble(c);
                for (int g = 0; g < n + 1; g++)
                {
                    c2 += b[g];
                }
                textBox1.Text = c2 + Math.Sqrt(c1);
            }
            else
            {
                textBox1.Text = Math.Sqrt(Convert.ToDouble(b)) + "";
            }
       
        }

        private void button20_Click(object sender, EventArgs e)
        {
            //按钮 求倒数
            string b = textBox1.Text;//一个简单的承接，把显示的字符串
            string c = "";
            string c2 = "";
            double c1 = 0;
            int n = 0;
            bool flag = true;//用来判断是不是只有一个数字
            for (int j = 0; j < b.Length; j++)
            {
                if (b[j].Equals('+') || b[j].Equals('-') || b[j].Equals('*') || b[j].Equals('/'))
                {
                    flag = false;
                    break;
                }
            }
            if (flag == false)
            {
                if (!b[b.Length - 1].Equals('+') && !b[b.Length - 1].Equals('-') && !b[b.Length - 1].Equals('*') && !b[b.Length - 1].Equals('/'))//只能是最后一个字符为数字是才能执行
                {
                    for (int k = b.Length - 1; k > -1; k--)
                    {
                        if (b[k].Equals('+') || b[k].Equals('-') || b[k].Equals('*') || b[k].Equals('/'))
                        {
                            n = k;
                            break;
                        }
                    }
                }
                for (int g = n; g < b.Length; g++)
                {
                    c += b[g];
                }
                c1 = Convert.ToDouble(c);
                for (int g = 0; g < n + 1; g++)
                {
                    c2 += b[g];
                }
                textBox1.Text = c2 + 1/c1;
            }
            else
            {
                textBox1.Text = 1/Convert.ToDouble(b) + "";
            }

        }

        private void button21_Click(object sender, EventArgs e)
        {
            //按钮 求倒数
            string b = textBox1.Text;//一个简单的承接，把显示的字符串
            string c = "";
            string c2 = "";
            double c1 = 0;
            int n = 0;
            bool flag = true;//用来判断是不是只有一个数字
            for (int j = 0; j < b.Length; j++)
            {
                if (b[j].Equals('+') || b[j].Equals('-') || b[j].Equals('*') || b[j].Equals('/'))
                {
                    flag = false;
                    break;
                }
            }
            if (flag == false)
            {
                if (!b[b.Length - 1].Equals('+') && !b[b.Length - 1].Equals('-') && !b[b.Length - 1].Equals('*') && !b[b.Length - 1].Equals('/'))//只能是最后一个字符为数字是才能执行
                {
                    for (int k = b.Length - 1; k > -1; k--)
                    {
                        if (b[k].Equals('+') || b[k].Equals('-') || b[k].Equals('*') || b[k].Equals('/'))
                        {
                            n = k;
                            break;
                        }
                    }
                }
                for (int g = n; g < b.Length; g++)
                {
                    c += b[g];
                }
                c1 = Convert.ToDouble(c);
                for (int g = 0; g < n + 1; g++)
                {
                    c2 += b[g];
                }
                textBox1.Text = c2 + Math.Sqrt(c1);
            }
            else
            {
                textBox1.Text = Math.Sqrt(Convert.ToDouble(b)) + "";
            }

        }

        private void button22_Click(object sender, EventArgs e)
        {
            //按钮 帮助
            new Form2().Show();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            textBox1.Text = "0";//让其一开始显示零
            textBox1.TextAlign = HorizontalAlignment.Right;//从右向左输入格式
        }

        private void textBox1_TextChanged(object sender, EventArgs e)
        {

        }
    }
}

代码整体思路介绍：

本程序的核心思想就是显示还有运算进行分离，先进性显示比如输入3+3*3

操作顺序为 按钮3 按钮+ 按钮3 按钮* 按钮3 按钮=

前边五个按钮的工作就是正确显示式子，然后都赋值给textBox1.Text也就是屏幕显示的text文本

然后在 = 按钮中进行了大量工作，

第一步将获取的textBox1.Text的值然后分开为数字集合还有运算符号集合

第二步根据数字集合中数字的数量来判定是两个数字的计算，还是三个数字的计算

第三步根据数字数组内容还有符号数组内容进行列举式计算

第四步清空俩个数组，然后输出结果

注意点：

1.在程序中创建了两个数组，用来存放数字还有符号

double[] number_double = new double[10];//数字集合

string[] operator_string = new string[10];//运算符集合

int numberxiabiao_int = 0;//数字集合下标

int operatorxiabiao_int = 0;//运算符下标

  当清空数组的时候是将下标变为0

2.在进行开根号还有求倒数的计算就是对式子最后一个数字或者只有一个数字的情况进行结果输出例如

1+4*9的情况 进行 开根号操作 就变成 1+4*3

9 变成 3

开根号或者求倒数部分就是如果不止一个数字就将最后一个数字截取出来，然后开根号或者求倒数再放回去

3.小数按钮只是显示。在分开为数字集合还有符号集合的时候，已经通过遇到运算符才终止本数字的读取的方法来识别了。

4.关于程序健壮性

（1）不能连续输入两个运算符，或者小数点。实现部分位置，在运算符还有小数点输入按钮中，通过读取上一个符号是不是运算符或者小于号来实现。

（2）除法除数不能为0。实现部位位置，数字输入函数public void numclik(int num)