calculator in c#

using System; 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 Windowaculator { public partial class Form1 : Form { public Form1() { InitializeComponent(); } float num1, ans; int count; private void btnc_Click(object sender, EventArgs e) { textBox1.Clear(); count = 0; } private void btnce_Click(object sender, EventArgs e) { if (num1 == 0 && textBox1.TextLength > 0) { num1 = 0; textBox1.Clear(); } else if (num1 > 0 && textBox1.TextLength > 0) { textBox1.Clear(); } } private void btnbackspace_Click(object sender, EventArgs e) { int lenght = textBox1.TextLength - 1; string text = textBox1.Text; textBox1.Clear(); for (int i = 0; i < lenght; i++) textBox1.Text = textBox1.Text + text[i]; } private void btnminus_Click(object sender, EventArgs e) { if (textBox1.Text != "") { num1 = float.Parse(textBox1.Text); textBox1.Clear(); textBox1.Focus(); count = 1; } } private void btn1_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 1; } private void btn2_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 2; } private void btn3_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 3; } private void btnplus_Click(object sender, EventArgs e) { num1 = float.Parse(textBox1.Text); textBox1.Clear(); textBox1.Focus(); count = 2; } private void btn4_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 4; } private void btn5_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 5; } private void btn6_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 6; } private void btnmultiply_Click(object sender, EventArgs e) { num1 = float.Parse(textBox1.Text); textBox1.Clear(); textBox1.Focus(); count = 3; } private void btn7_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 7; } private void btn8_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 8; } private void btn9_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 9; } private void btndivied_Click(object sender, EventArgs e) { num1 = float.Parse(textBox1.Text); textBox1.Clear(); textBox1.Focus(); count = 4; } private void btn0_Click(object sender, EventArgs e) { textBox1.Text = textBox1.Text + 0; } private void btnpoint_Click(object sender, EventArgs e) { int c = textBox1.TextLength; int flag = 0; string text = textBox1.Text; for (int i = 0; i < c; i++) { if (text[i].ToString() == ".") { flag = 1; break; } else { flag = 0; } } if (flag == 0) { textBox1.Text = textBox1.Text + "."; } } private void btnequal_Click(object sender, EventArgs e) { compute(count); } public void compute(int count) { switch (count) { case 1: ans = num1 - float.Parse(textBox1.Text); textBox1.Text = ans.ToString(); break; case 2: ans = num1 + float.Parse(textBox1.Text); textBox1.Text = ans.ToString(); break; case 3: ans = num1 * float.Parse(textBox1.Text); textBox1.Text = ans.ToString(); break; case 4: ans = num1 / float.Parse(textBox1.Text); textBox1.Text = ans.ToString(); break; case 5: ans = num1 % float.Parse(textBox1.Text); textBox1.Text = ans.ToString(); break; default: break; } } private void button1_Click(object sender, EventArgs e) { num1 = float.Parse(textBox1.Text); textBox1.Clear(); textBox1.Focus(); count = 5; } } }