protected void Repeater1_ItemCommand(object source, RepeaterCommandEventArgs e)
    {
        string id = e.CommandArgument.ToString();

        if (e.CommandName == "Delete")
        {
            ProductsOrServices = ProductsOrServices.Where(a => a.ModifiedID.ToString() != id).ToList();
            BindRepeater();
        }
    }
    protected void btnAdd_Click(object sender, EventArgs e)
    {
        if (Validate())
        {
            int order = ProductsOrServices.Count + 1;
            ProductsOrServices.Add(new tblProductOrService()
            {
                CampaignID       = this.CampaignID,
                ProductOrService = tbProductOrService.Text.Trim(),
                SearchPhraseForProductOrService = tbSearchPhrase.Text.Trim(),
                ModifiedID = DateTime.Now.Ticks.ToString()
            });
            tbSearchPhrase.Text     = string.Empty;
            tbProductOrService.Text = string.Empty;

            BindRepeater();
        }
    }