Листинг 2. Как написать простой калькулятор ч.2

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
 
namespace SimpleCalc
{
    public partial class FormCalculate : Form
    {
        private Calculate cl;
        string strNum = "";
        public FormCalculate()
        {
            InitializeComponent();
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
            cl = new Calculate(this);
        }
 
        private void btNum1_Click(object sender, EventArgs e)
        {
            enterNum(btNum1.Text);
        }
 
        private void btNum2_Click(object sender, EventArgs e)
        {
            enterNum(btNum2.Text);
        }
 
        private void btNum3_Click(object sender, EventArgs e)
        {
            enterNum(btNum3.Text);
        }
 
        private void btNum4_Click(object sender, EventArgs e)
        {
            enterNum(btNum4.Text);
        }
 
        private void btNum5_Click(object sender, EventArgs e)
        {
            enterNum(btNum5.Text);
        }
 
        private void btNum6_Click(object sender, EventArgs e)
        {
            enterNum(btNum6.Text);
        }
 
        private void btNum7_Click(object sender, EventArgs e)
        {
            enterNum(btNum7.Text);
        }
 
        private void btNum8_Click(object sender, EventArgs e)
        {
            enterNum(btNum8.Text);
        }
 
        private void btNum9_Click(object sender, EventArgs e)
        {
            enterNum(btNum9.Text);
        }
 
        private void btMinus_Click(object sender, EventArgs e)
        {
 
            enterAction(btMinus.Text);
        }
 
        private void btNum0_Click(object sender, EventArgs e)
        {
            enterNum(btNum0.Text);
        }
 
        private void btPlus_Click(object sender, EventArgs e)
        {
            enterAction(btPlus.Text);
        }
 
        private void btCount_Click(object sender, EventArgs e)
        {
            cl.ChoiceMethod(strNum);
            string answ=cl.Count();
            this.txtWatch.Text += " = " + answ;
            strNum = answ;
            listLog.Items.Add(cl.LineLog);
        }
        private void btShare_Click(object sender, EventArgs e)
        {
            enterAction(btShare.Text);
        }
 
        private void btMultiply_Click(object sender, EventArgs e)
        {
            enterAction(btMultiply.Text);
        }
        private void enterNum(string num)
        {
            this.txtWatch.Text += num;
            strNum += num;
        }
        private void enterAction(string tag)
        {
            cl.ChoiceMethod(strNum);
            cl.ChoiceMethod(tag);
            strNum = "";
            txtWatch.Text += strNum + " " + tag + " ";
        }
 
        private void txtWatch_TextChanged(object sender, EventArgs e)
        {
            if (txtWatch.Text == "")
            {
                strNum = "";
            }
        }
 
        private void btClear_Click(object sender, EventArgs e)
        {
            txtWatch.Clear();
        }
    }
}