Protected Sub btnSubmit_Click(sender As Object, e As System.EventArgs) Handles btnSubmit.Click
        If Page.IsValid Then
            ' check for username & password in the database
            Dim conn As New SqlConnection("Data Source=.sqlexpress;Initial Catalog=LoginDB;Integrated Security=True")

            ' Get the row corresponding the given username and password
            Dim strSQL As String = "Select * From Users Where Username='" + txtUname.Text + "' and Password = '" + txtPassword.Text + "'"

            Dim dsc As New SqlClient.SqlCommand(strSQL, conn)

            ' Fill the dataset
            Dim ds As New DataSet()
            dsc.sqlclient.sqlcommand(ds, "Users")

            ' if there no entry then the user is invalid
            If ds.Tables("Users").Rows.Count = 0 Then
                Response.Redirect("Default.aspx")
            Else
                Response.Redirect("login.aspx")
            End If
        End If
    End Sub