private void Search() { SqlString CustomerName = SqlString.Null; SqlString MobileNumber = SqlString.Null; SqlString EmailAddress = SqlString.Null; if (txtSearchCustomerName.Text.Trim() != "") { CustomerName = Convert.ToString(txtSearchCustomerName.Text.Trim()); } if (txtSerachEmail.Text.Trim() != "") { EmailAddress = Convert.ToString(txtSerachEmail.Text.Trim()); } if (txtSearchMobileNumber.Text.Trim() != "") { MobileNumber = Convert.ToString(txtSearchMobileNumber.Text.Trim()); } CustomerBAL balCustomer = new CustomerBAL(); DataTable dtCustomer = balCustomer.Search(CustomerName, MobileNumber, EmailAddress); if (dtCustomer != null && dtCustomer.Rows.Count > 0) { gvCustomer.DataSource = dtCustomer; gvCustomer.DataBind(); } else { gvCustomer.DataSource = null; gvCustomer.DataBind(); } }