Shawn

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

namespace GaryCalculator
{
    public partial class Form1 : Form
    {
        List<float> numbers = new List<float>();

        public Form1()
        {
            InitializeComponent();
        }

        private void Total()
        {
            float answer = 0;

            foreach (float number in numbers)
            {
                answer += number;
            }
            lblOutput.Text = answer.ToString();
            numbers.Clear();
        }

        private void Form1_KeyPress(object sender, KeyPressEventArgs e)
        {
            MessageBox.Show(e.KeyChar.ToString());
        }

        private void Form1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter || e.KeyCode == Keys.Return)
            {
                MessageBox.Show("Enter key");
            }
            if (e.KeyCode == Keys.C)
            {
                lblOutput.Text = "";
                numbers.Clear();
            }
            else if (e.KeyCode == Keys.D0 || e.KeyCode == Keys.NumPad0)
                lblOutput.Text += "0";
            else if (e.KeyCode == Keys.D1 || e.KeyCode == Keys.NumPad1)
                lblOutput.Text += "1";
            else if (e.KeyCode == Keys.D2 || e.KeyCode == Keys.NumPad2)
                lblOutput.Text += "2";
            else if (e.KeyCode == Keys.D3 || e.KeyCode == Keys.NumPad3)
                lblOutput.Text += "3";
            else if (e.KeyCode == Keys.D4 || e.KeyCode == Keys.NumPad4)
                lblOutput.Text += "4";
            else if (e.KeyCode == Keys.D5 || e.KeyCode == Keys.NumPad5)
                lblOutput.Text += "5";
            else if (e.KeyCode == Keys.D6 || e.KeyCode == Keys.NumPad6)
                lblOutput.Text += "6";
            else if (e.KeyCode == Keys.D7 || e.KeyCode == Keys.NumPad7)
                lblOutput.Text += "7";
            else if (e.KeyCode == Keys.D8 || e.KeyCode == Keys.NumPad8)
                lblOutput.Text += "8";
            else if (e.KeyCode == Keys.D9 || e.KeyCode == Keys.NumPad9)
                lblOutput.Text += "9";
            else if (e.KeyCode == Keys.Decimal)
            {
                if (!lblOutput.Text.Contains("."))
                    lblOutput.Text += ".";
            }
            else if (e.KeyCode == Keys.Add)
            {
                MessageBox.Show("Add");
            }
            else if (e.KeyCode == Keys.Subtract)
            {
                MessageBox.Show("Subtract");
            }
        }

        private void Form1_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
        {
            MessageBox.Show(e.KeyCode.ToString());
        }
    }
}