Design a calculator for Windows C#.NET

 Nagpur University MCA V Semester, C#.Net, Embedded System Programming, Nagpur University Practical MCA V SEM , Design a calculator for Windows C#.NET

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

namespace calc
{
    public partial class Form1 : Form
    {
        double op1, op2, ans;
        string str;
        int len,oprator;
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            txtDisplay.Text = "0";
        }

        private void btnOne_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text=="+" || txtDisplay.Text=="-" || txtDisplay.Text=="*" || txtDisplay.Text=="/" || txtDisplay.Text=="%")
                txtDisplay.Text = "1";
            else
                txtDisplay.Text = txtDisplay.Text + "1";
        }

        private void btnTwo_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "2";
            else
                txtDisplay.Text = txtDisplay.Text + "2";
        }

        private void btnThree_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "3";
            else
                txtDisplay.Text = txtDisplay.Text + "3";
        }

        private void btnFour_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "4";
            else
                txtDisplay.Text = txtDisplay.Text + "4";
        }

        private void btnFive_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "5";
            else
                txtDisplay.Text = txtDisplay.Text + "5";
        }

        private void btnSix_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "6";
            else
                txtDisplay.Text = txtDisplay.Text + "6";
        }

        private void btnSeven_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "7";
            else
                txtDisplay.Text = txtDisplay.Text + "7";
        }

        private void btnEight_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "8";
            else
                txtDisplay.Text = txtDisplay.Text + "8";
        }

        private void btnNine_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "9";
            else
                txtDisplay.Text = txtDisplay.Text + "9";
        }

        private void btnZero_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "0";
            else
                txtDisplay.Text = txtDisplay.Text + "0";
        }

        private void btnZeroZero_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "0";
            else
                txtDisplay.Text = txtDisplay.Text + "00";
        }

        private void btnPoint_Click(object sender, EventArgs e)
        {
            if (txtDisplay.Text == "0" || txtDisplay.Text == "+" || txtDisplay.Text == "-" || txtDisplay.Text == "*" || txtDisplay.Text == "/" || txtDisplay.Text == "%")
                txtDisplay.Text = "0.";
            else
                txtDisplay.Text = txtDisplay.Text + ".";
        }

        private void btnAllClear_Click(object sender, EventArgs e)
        {
            txtDisplay.Text = "0";
        }

        private void btnDivide_Click(object sender, EventArgs e)
        {
            op1 = Convert.ToDouble(txtDisplay.Text);
            txtDisplay.Text = "/";
            oprator = 1;
        }

        private void btnMultiply_Click(object sender, EventArgs e)
        {
            op1 = Convert.ToDouble(txtDisplay.Text);
            txtDisplay.Text = "*";
            oprator = 2;
        }

        private void btnAddition_Click(object sender, EventArgs e)
        {
            op1 = Convert.ToDouble(txtDisplay.Text);
            txtDisplay.Text = "+";
            oprator = 3;
        }

        private void btnSubtract_Click(object sender, EventArgs e)
        {
            op1 = Convert.ToDouble(txtDisplay.Text);
            txtDisplay.Text = "-";
            oprator = 4;
        }

        private void btnPercent_Click(object sender, EventArgs e)
        {
            op1 = Convert.ToDouble(txtDisplay.Text);
            txtDisplay.Text = "%";
            oprator = 5;
        }

        private void btnEqual_Click(object sender, EventArgs e)
        {
            op2 = Convert.ToDouble(txtDisplay.Text);
            switch (oprator)
            {
                case 1:
                    ans = op1 / op2;
                    break;
                case 2:
                    ans = op1 * op2;
                    break;
                case 3:
                    ans = op1 + op2;
                    break;
                case 4:
                    ans = op1 - op2;
                    break;
                case 5:
                    ans = (op1 * 100) / op2;
                    break;
            }
            txtDisplay.Text = Convert.ToString(ans);
        }

        private void btnClear_Click(object sender, EventArgs e)
        {
            len  = txtDisplay.Text.Length;
            if (len != 0)
                str = txtDisplay.Text.Remove(len - 1, 1);
            else
                txtDisplay.Text = "0";
            txtDisplay.Text = str;
        }
    }
}

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Nagpur University MCA V Semester, C#.Net, Embedded System Programming, Nagpur University Practical MCA V SEM