Datagrid and database

I have a form consisting of datagridview and two buttons of update and load all.. I have used fillby method to obtain data from database. The query seems to be working fine, except that the data is not shown in the gridview.

As in, for the query, if the returned rows are 2, it will show 3 rows in the gridview, but all empty.

Imports System.Data
Imports System.Data.OleDb
Imports System.EventArgs
Imports System.Data.OleDb.OleDbConnection
Imports System.Data.OleDb.OleDbCommand

Public Class Form1
    Inherits System.Windows.Forms.Form

    Dim wrkdir As String = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly.Location())
    Dim da As New OleDbDataAdapter
    Dim ds As New DataSet
    Dim bs As New BindingSource
    Dim edit As Boolean
    'Dim cnn As OleDbConnection


    Dim cnn As New OleDbConnection("Provider=microsoft.jet.oledb.4.0;Data Source=E:\Project-Hemtech\HemDatabase1.mdb;")

    'cnn = New OleDbConnection("Provider=microsoft.jet.oledb.4.0;Data Source=E:\Project-Hemtech\HemDatabase1.mdb;")
    'cnn.Open()

    Private Sub button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button1.Click

        If edit Then
            da.Update(ds, "partno")
            edit = False
        End If

    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.L开发者_如何学编程oad
        'TODO: This line of code loads data into the 'HemDatabase1DataSet.partno' table. You can move, or remove it, as needed.
        Me.PartnoTableAdapter.Fill(Me.HemDatabase1DataSet.partno)

        dgv1.DataSource = bs

        'Dim cnn As New OleDbConnection("Provider=microsoft.jet.oledb.4.0;Data Source=E:\Project-Hemtech\HemDatabase1.mdb;")
        'cnn = New OleDbConnection("Provider=microsoft.jet.oledb.4.0;Data Source=E:\Project-Hemtech\HemDatabase1.mdb;")
        'cnn.Open()

    End Sub

    Private Sub button2_click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button2.Click

        ds.Tables.Clear()

        If tsText.Text <> "" Then

            Dim sql As String = "SELECT partno.partnum, partno.partname, partno.partdesc, partno.partqty " & _
                                "FROM(partno)" & _
                                "WHERE (((partno.type)='" & tsText.Text & "'));"

            Dim cmd As New OleDbCommand(sql, cnn)

            da.SelectCommand = cmd

            Dim cmdBuilder As New OleDbCommandBuilder(da)

            da.Fill(ds, "partno")
            bs.DataSource = ds.Tables(0)

        Else

            Exit Sub

        End If
    End Sub

    Private Sub button3_Click(ByVal sender As System.Object, ByVal e As EventArgs) Handles button3.Click

        ds.Tables.Clear()

        Dim sql As String = "SELECT * FROM partno;"
        Dim cmd As New OleDbCommand(sql, cnn)

        da.SelectCommand = cmd

        Dim cmdbuilder As New OleDbCommandBuilder(da)
        da.Fill(ds, "partno")
        bs.DataSource = ds.Tables(0)

    End Sub

    Private Sub FillByToolStripButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button3.Click
        Try
            Me.PartnoTableAdapter.FillBy(Me.HemDatabase1DataSet.partno, tsText.Text)
        Catch ex As System.Exception
            System.Windows.Forms.MessageBox.Show(ex.Message)
        End Try

    End Sub
End Class

you should add dgv1.DataSource = bs on every button events so that the data on the GridView will update