title: Adding DataRow one by one to DataTable
body: <p>I have a webform for entering Invoice info to a DB.</p>
  
  <p>I have 3 textboxes requesting product quantity, product and price.</p>
  
  <p>I decided to create a DataTable to store temporarily quantity, productId, price so that the user might add N products for later saving the data on the DataTable (displayed on a grid) to the DB.</p>
  
  <p>I don't know what am I doing wrong but am unable to store a second product. After I save 1 row to the DataTable the second one is not added but overwrites the first one. I know this has to be something really stupid on my part but haven´t been able to figure out what am I doing wrong and am sort of a beginner.</p>
  
  <pre><code>Public Class IngresoFacturas
      Inherits System.Web.UI.Page
      Dim miDataTable = New DataTable
  
      Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
          miDataTable.Columns.Add("dCantidad", GetType(System.Int32))
          miDataTable.Columns.Add("idProducto", GetType(System.Int32))
          miDataTable.Columns.Add("mTotal", GetType(System.Decimal))
  
      End Sub
  
      Protected Sub RadButton1_Click(sender As Object, e As EventArgs) Handles RadButton1.Click
  
          miDataTable.Rows.Add(RadNumericTextBox2.Text, Int32.Parse(RadAutoCompleteBox2.Entries.Item(0).Value), RadNumericTextBox3.Text)
          RadGrid1.Rebind() 'Forces rebind to update Grid
          RadAutoCompleteBox2.Entries.Clear()
          RadNumericTextBox2.Text = ""
          RadNumericTextBox3.Text = ""
  
      End Sub
  
      Protected Sub RadGrid1_NeedDataSource(sender As Object, e As Telerik.Web.UI.GridNeedDataSourceEventArgs) Handles RadGrid1.NeedDataSource
  
          RadGrid1.DataSource = miDataTable
  
      End Sub
  End Class
  </code></pre>