private string Item_Alumno_GetByCurso()
    {
        var    instance   = CustomerFramework.Load("AMPA");
        string res        = "[]";
        var    parameters = new List <SqlParameter>
        {
            DataParameter.Input("@CursoId", Convert.ToInt64(this.Request.QueryString["CursoId"]))
        };

        try
        {
            res = SqlStream.GetSqlStream("Item_Alumno_GetByCurso", new ReadOnlyCollection <SqlParameter>(parameters), instance.Config.ConnectionString);
        }
        catch (Exception ex)
        {
            ExceptionManager.Trace(ex, "Item_Alumno_GetByCurso(" + Convert.ToInt64(this.Request.QueryString["CursoId"]) + ")");
        }

        return(res);
    }