SqlDataSource ใส่ค่า sql command ในส่วนของ Code behide

    <asp:SqlDataSource ID="SqlDataSourceForAutoComplete" runat="server" ConnectionString="<%$ ConnectionStrings:defaultDatabase %>" 
      >
    </asp:SqlDataSource>

SqlDataSource1.SelectCommand =
               @"SELECT [ID], [Phone], [FirstName], [LastName] FROM (select [ID], [Phone], [FirstName], [LastName], row_number()over(order by t.[LastName]) as [rn] from [Persons] as t where (([FirstName] + ' ' + [LastName] + ' ' + [Phone]) LIKE @filter)) as st where st.[rn] between @startIndex and @endIndex";

        SqlDataSource1.SelectParameters.Clear();
        SqlDataSource1.SelectParameters.Add("filter", TypeCode.String, string.Format("%{0}%", e.Filter));
        SqlDataSource1.SelectParameters.Add("startIndex", TypeCode.Int64, (e.BeginIndex + 1).ToString());
        SqlDataSource1.SelectParameters.Add("endIndex", TypeCode.Int64, (e.EndIndex + 1).ToString());
        comboBox.DataSource = SqlDataSource1;
        comboBox.DataBind();