利用字符串作为参数创建接口实例

//BLL.DJTxtImportBll txtImportBLL = new BLL.DJTxtImportBll();
//IBLL.IDJTxtImportBll txtImportBLL = Factory.BLLFactory.CreateInstant<IBLL.IDJTxtImportBll>("DJTxtImportBll");