Imports Microsoft.VisualBasic
Imports System.Data.SqlClient
Public Class FrmControlsPractice
    Dim con As SqlConnection
    Dim cmd As SqlCommand
    Dim dr As SqlDataReader
    Dim dt As New DataTable
    Private Sub FrmControlsPractice_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Label1.Text = "BackGroundProcess started at" & Now.minutes & ":" & Now.Seconds()
        ComboBox1.CheckForIllegalCrossThreadCalls = False
        bw.RunWorkerAsync()
    End Sub

    Private Sub bw_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles bw.DoWork
        con = New SqlConnection("Data Source=VIDYA;Initial Catalog=master;Persist Security Info=True;User ID=sa;password=manager")
        cmd = New SqlCommand("select * from emp", con)
        con.Open()
        dr = cmd.ExecuteReader(CommandBehavior.CloseConnection)
        While dr.Read
            Me.ComboBox1.Items.Add(dr(0))
            Threading.Thread.Sleep(2000)  '2 seconds
        End While

    End Sub

    Private Sub bw_RunWorkerCompleted(ByVal sender As Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles bw.RunWorkerCompleted
        Label2.Text = "BackGroundProcess stopped at" & Now.minutes & ":" & Now.Seconds()
        Label3.Text = "background work completed"
    End Sub
End Class