How use RadioButton, ComboBox, CheckBox, ListBox & GroupBox in Visual c#.net

Develop an application with one screen that calculates the monthly salary of an employee. Your application should satisfy the following requirements:

1.      Make sure you use all of the following components:
Label, TextBox, RadioButton, ComboBox, CheckBox, ListBox, Button, GroupBox

2.      Employee Name: (TextBox)

3.      Employee Grade Level: (ComboBox)
Director, Manager, Project Manager, Programmer

4.      Basic Salary: (RadioButton)
30,000, 40,000, 50,000, 100,000

Basic Salary value should be read only and automatically selected based on the selected Employee Grade Level

5.      Benefits: (CheckBox)
Housing Allowance, Conveyance Allowance, Other Benefit 1, Other Benefit 2
(20000, 15000, 10000, 10000 respectively)

6.      Bonuses: (ListBox)
Project Completion Bonus, Year End Bonus, Performance Bonus, Customer appreciation Bonus
(20000, 30000, 25000, 15000)

7.      Deductions: TextBox
Provident Fund Deduction, Medical Deduction

8.      Calculate the Salary based on the user input regarding above features and display the result

9.      An Exit button

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; using ClassLibrary1; namespace lab3 { public partial class Form1 : Form { public Form1() { InitializeComponent(); cal.Enabled = false; } private void Ext_Click(object sender, EventArgs e) { this.Close(); } private void cal_Click(object sender, EventArgs e) { int sal = 0; sal += int.Parse(cb2.Text); if (c1.Checked == true) sal += 5000; if (c2.Checked == true) sal += 5000; if (c3.Checked == true) sal += 5000; if (c4.Checked == true) sal += 5000; sal += (10000 * lb1.SelectedIndices.Count); if (c5.Checked == true) sal -= 1500; if (c6.Checked == true) sal -= 2500; tb2.Text = sal.ToString(); } private void cb2_SelectedIndexChanged(object sender, EventArgs e) { if (tb1.Text != "" && cb1.SelectedIndex >= 0 && (r1.Checked == true || r2.Checked == true) && cb2.SelectedIndex >= 0 && lb1.SelectedIndices.Count > 0) cal.Enabled = true; } private void cb1_SelectedIndexChanged(object sender, EventArgs e) { if (cb1.SelectedIndex == 0) cb2.SelectedIndex = 4; if (cb1.SelectedIndex == 1) cb2.SelectedIndex = 3; if (cb1.SelectedIndex == 2) cb2.SelectedIndex = 2; if (cb1.SelectedIndex == 3) cb2.SelectedIndex = 1; if (tb1.Text != "" && cb1.SelectedIndex >= 0 && (r1.Checked == true || r2.Checked == true) && cb2.SelectedIndex >= 0 && lb1.SelectedIndices.Count > 0) cal.Enabled = true; } private void tb1_TextChanged(object sender, EventArgs e) { if (tb1.Text != "" && cb1.SelectedIndex >= 0 && (r1.Checked == true || r2.Checked == true) && cb2.SelectedIndex >= 0 && lb1.SelectedIndices.Count > 0) cal.Enabled = true; } private void gb1_Enter(object sender, EventArgs e) { } private void lb1_SelectedIndexChanged(object sender, EventArgs e) { if (tb1.Text != "" && cb1.SelectedIndex >= 0 && (r1.Checked == true || r2.Checked == true) && cb2.SelectedIndex >= 0 && lb1.SelectedIndices.Count > 0) cal.Enabled = true; } private void r1_CheckedChanged(object sender, EventArgs e) { if (tb1.Text != "" && cb1.SelectedIndex >= 0 && (r1.Checked == true || r2.Checked == true) && cb2.SelectedIndex >= 0 && lb1.SelectedIndices.Count > 0) cal.Enabled = true; } private void r2_CheckedChanged(object sender, EventArgs e) { if (tb1.Text != "" && cb1.SelectedIndex >= 0 && (r1.Checked == true || r2.Checked == true) && cb2.SelectedIndex >= 0 && lb1.SelectedIndices.Count > 0) cal.Enabled = true; } private void button1_Click(object sender, EventArgs e) { Class1 asd = new Class1(); int x = asd.fn(3); tb1.Text = x.ToString(); } } }