sht2

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;
using StudentNamespace;
using StudentInformationApplication;

namespace StudentInformationApplication
{
    public partial class Form1 : Form
    {

        public Form1()
        {
            InitializeComponent();
        }

        private void btn_submit_Click(object sender, EventArgs e)
        {
            StudentInfo student = new StudentInfo(tb_sid.Text, tb_ln.Text, tb_fn.Text);

            if (student.validate())
            {
                lb_sid.Items.Add(student.Sid);
                lb_ln.Items.Add(student.Lname);
                lb_fn.Items.Add(student.Fname);
            }
            else
            {
                MessageBox.Show("Check your input", "text box values error");
            }
        }
    }
}