SuperLemrick's Calculator Source Code

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 Calculator
{
    public partial class CalculatorForm : Form
    {
        int firstNum = 0;
        int result = 0;
        bool addButtonFlag = false;
        bool subtractButtonFlag = false;
        bool multiplyButtonFlag = false;
        bool divideButtonFlag = false;
        public CalculatorForm()
        {
            InitializeComponent();
        }

        private void One_Click(object sender, EventArgs e)
        {
            InputBox.Text += "1";
        }

        private void Two_Click(object sender, EventArgs e)
        {
            InputBox.Text += "2";
        }

        private void Three_Click(object sender, EventArgs e)
        {
            InputBox.Text += "3";
        }

        private void Four_Click(object sender, EventArgs e)
        {
            InputBox.Text += "4";
        }

        private void Five_Click(object sender, EventArgs e)
        {
            InputBox.Text += "5";
        }

        private void Six_Click(object sender, EventArgs e)
        {
            InputBox.Text += "6";
        }

        private void Seven_Click(object sender, EventArgs e)
        {
            InputBox.Text += "7";
        }

        private void Eight_Click(object sender, EventArgs e)
        {
            InputBox.Text += "8";
        }

        private void Nine_Click(object sender, EventArgs e)
        {
            InputBox.Text += "9";
        }

        private void Zero_Click(object sender, EventArgs e)
        {
            InputBox.Text += "0";
        }

        private void ClearEverything_Click(object sender, EventArgs e)
        {
            result = 0;
            firstNum = 0;
            InputBox.Text = "";
            addButtonFlag = false;
            subtractButtonFlag = false;
        }

        private void Plus_Click(object sender, EventArgs e)
        {
            if (InputBox.Text != "")
            {
                firstNum = int.Parse(InputBox.Text);
                InputBox.Text = "";
                addButtonFlag = true;
            }
            else
            {
                MessageBox.Show("You must enter a number!");
            }
        }

        private void Minus_Click(object sender, EventArgs e)
        {
            if (InputBox.Text != "")
            {
                firstNum = int.Parse(InputBox.Text);
                InputBox.Text = "";
                subtractButtonFlag = true;
            }
            else
            {
                MessageBox.Show("You must enter a number!");
            }
        }

         private void Multiply_Click(object sender, EventArgs e)
        {
            if (InputBox.Text != "")
            {
                firstNum = int.Parse(InputBox.Text);
                InputBox.Text = "";
                multiplyButtonFlag = true;
            }
            else
            {
                MessageBox.Show("You must enter a number!");
            }
        }

         private void Divide_Click(object sender, EventArgs e)
         {
             if (InputBox.Text != "")
             {
                 firstNum = int.Parse(InputBox.Text);
                 InputBox.Text = "";
                 divideButtonFlag = true;
             }
             else
             {
                 MessageBox.Show("You must enter a number!");
             }
         }

        private void Equals_Click(object sender, EventArgs e)
        {
            int secondNum = int.Parse(InputBox.Text);
            {
                if (InputBox.Text != "")
                {
                    if (addButtonFlag == true)

                        result = firstNum + secondNum;

                    else if (subtractButtonFlag == true)

                        result = firstNum - secondNum;

                    else if (divideButtonFlag == true)

                        result = firstNum / secondNum;

                    else if (multiplyButtonFlag == true)

                        result = firstNum * secondNum;

                    InputBox.Text = result.ToString();
                 }
             }
         }
    }
}