C# 윈폼 계산기

만들어본 계산기

using System;
using System.Collections;
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 WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        
        private bool newButton;   // 새로 숫자가 시작되어야 하는 것을 말하는 flag
       
        private string number1, number2;

        private int Cal = 0;

        public Form1()
        {
            InitializeComponent();
        }

        private void btn1_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "1";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "1";
                txtResult1.Text = number2;
            }
        }
        private void btn2_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "2";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "2";
                txtResult1.Text = number2;
            }
        }
        private void btn3_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "3";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "3";
                txtResult1.Text = number2;
            }
        }
        private void btn4_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "4";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "4";
                txtResult1.Text = number2;
            }
        }
        private void btn5_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "5";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "5";
                txtResult1.Text = number2;
            }
        }
        private void btn6_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "6";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "6";
                txtResult1.Text = number2;
            }
        }
        private void btn7_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "7";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "7";
                txtResult1.Text = number2;
            }
        }
        private void btn8_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "8";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "8";
                txtResult1.Text = number2;
            }
        }
        private void btn9_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "9";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "9";
                txtResult1.Text = number2;
            }
        }
        private void btn0_Click(object sender, EventArgs e)
        {
            if (newButton == false)
            {
                number1 += "0";
                txtResult1.Text = number1;
            }
            else
            {
                number2 += "0";
                txtResult1.Text = number2;
            }
        }

        private void btnMulti_Click(object sender, EventArgs e)
        {
            newButton = true;
            textBox1.Text = number1 + " * ";
            Cal = 1;
        }

        private void btnDiv_Click(object sender, EventArgs e)
        {
            newButton = true;
            textBox1.Text = number1 + " / ";
            Cal = 2;
        }

        private void btnPlus_Click(object sender, EventArgs e)
        {
            newButton = true;
            textBox1.Text = number1 + " + ";
            Cal = 3;
        }


       

        private void btnMin_Click(object sender, EventArgs e)
        {
            newButton = true;
            textBox1.Text = number1 + " - ";
            Cal = 4;
        }

        private void btnequal_Click_1(object sender, EventArgs e)
        {
            double num1 = System.Convert.ToDouble(number1);
            double num2 = System.Convert.ToDouble(number2);
            double result;

            if (Cal == 1)
            {
                textBox1.Text = number1 + "*" + number2 + "=";
                result = num1 * num2;
                txtResult1.Text = result.ToString();
            }
            else if (Cal == 2)
            {
                textBox1.Text = number1 + "/" + number2 + "=";
                result = num1 / num2;
                txtResult1.Text = result.ToString();
            }
            else if (Cal == 3)
            {
                textBox1.Text = number1 + "+" + number2 + "=";
                result = num1 + num2;
                txtResult1.Text = result.ToString();
            }
            else if (Cal == 4)
            {
                textBox1.Text = number1 + "-" + number2 + "=";
                result = num1 - num2;
                txtResult1.Text = result.ToString();
            }

            
        }
        private void button1_Click(object sender, EventArgs e)
        {
            number1 = "";
            number2 = "";
            txtResult1.Text = "";
            textBox1.Text = "";
        }

        



    }
}

 

각종 오류에 대한 수정이 필요하다.