code error

See more:

VB

I have a code of button next :

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim conn As New SqlConnection("data source=localhost;initial catalog=thinghiem;user=sa;pwd=sa")
        conn.Open()
        Dim dt As New DataTable
        Dim da As New SqlDataAdapter("select*from SINHVIEN", conn)
        da.Fill(dt)
        DataGridView1.DataSource = dt
        Me.BindingContext.Item(dt).Position = Me.BindingContext.Item(dt).Position + 1
    End Sub

why when I press the next button that DataGridView just scroll down the second line