sample.vb

Public Class frm_customer_orderproduct
    Dim current_id As String
    'NEW CODE IS HERE
    Dim dt As New DataTable
    Private Sub frm_customer_orderproduct_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        'Dim regDate As Date = Date.Today()
        
        'NEW CODE IS HERE
        dt.Columns.Add("Product ID")
        dt.Columns.Add("Product Name")
        dt.Columns.Add("Price")
        dt.Columns.Add("Quantity")
        
        
        lbl_user.Text = "Hi, " & custName & "!"

        refresh_grid()
        get_current_id()
    End Sub
    Private Sub refresh_grid()
        Dim mysql As String = "SELECT FLD_PRODUCT_ID, FLD_PRODUCT_NAME, FLD_PRODUCT_PRICE FROM TBL_PRODUCTS"
        Dim mydatatable As New DataTable
        Dim myreader As New OleDb.OleDbDataAdapter(mysql, myconnection)
        myreader.Fill(mydatatable)
        grd_product.DataSource = mydatatable
    End Sub
    Private Sub clear_fields()
        txt_id.Text = ""
        txt_name.Text = ""
        txt_price.Text = ""
        txt_qty.Text = ""
    End Sub
    Private Sub get_current_id()
        Dim current_row As Integer = grd_product.CurrentRow.Index
        current_id = grd_product(0, current_row).Value

        txt_id.Text = current_id
        txt_name.Text = grd_product(1, current_row).Value
        txt_price.Text = grd_product(2, current_row).Value
    End Sub

    Private Sub grd_product_CellClick(sender As Object, e As System.Windows.Forms.DataGridViewCellEventArgs) Handles grd_product.CellClick
        get_current_id()
    End Sub

    Private Sub btn_add_Click(sender As System.Object, e As System.EventArgs) Handles btn_add.Click
        If txt_qty.Text = "" Then
            MsgBox("Please insert quantity")
        Else
            
             Dim dr As DataRow
            dr = dt.NewRow
      
            dr(0) = txt_id.Text
            dr(1) = txt_name.Text
            dr(2) = txt_price.Text
            dr(3) = txt_qty.Text
            dt.Rows.Add(dr)
            grd_order.DataSource = dt

        End If

    End Sub
End Class