using System;
using System.Windows.Forms;
using System.Drawing;
using System.Data.SqlClient;

class ex : Form
{
    Label lb1 = new Label();
    Label lb2 = new Label();
    Label lb3 = new Label();
    TextBox tb1 = new TextBox();
    TextBox tb2 = new TextBox();
    TextBox tb3 = new TextBox();
    Button b1 = new Button();

    ex()
    {
        Text = "Customer entry";
        lb1.Text = "CustomerID:";
        lb2.Text = "First Name:";
        lb3.Text = "Last Name:";
        lb2.Location = new Point(0, 25);
        lb3.Location = new Point(0, 50);
        Controls.Add(lb1);
        Controls.Add(lb2);
        Controls.Add(lb3);
        tb1.Location = new Point(100, 0);
        tb2.Location = new Point(100, 25);
        tb3.Location = new Point(100, 50);
        Controls.Add(tb1);
        Controls.Add(tb2);
        Controls.Add(tb3);
        b1.Text = "return";
        b1.Click += new EventHandler(button_b1_click);
        b1.Location = new Point(200, 0);
        Controls.Add(b1);
    }

    void button_b1_click(object sender, EventArgs e)
    {
        SqlConnection conn = new SqlConnection("Data Source = (localdb)\\sql;" +
                                  "User id= sample_user;" +
                                  "Password = 'abc'; " +
                                  "Database = ex;");
        conn.Open();
        SqlCommand command = new SqlCommand(
                                  "select CustomerID, FirstName, LastName " +
                                  "from Customers " +
                                  "where CustomerID = 3", conn);

        SqlDataReader reader = command.ExecuteReader();
        reader.Read();
        tb1.Text = reader[0].ToString();
        tb2.Text = reader[1].ToString();
        tb3.Text = reader[2].ToString();
        conn.Close();
    }


    static public void Main()
    {
        Application.Run(new ex());
    }
}