The following is a structure diagram of DAF:
Does it seem to be relatively simple?
According to past experience, in this inheritance mode, the main development work is fully concentrated on Dafbase and MyDaf, and the task of CustomerDAF is relatively easy. Data checks or conversion processing is not every method.
So, since it is known as Façade, in addition to meeting the necessary conditions of façade, it has a good appearance, making an example for the above Data Entity Façade and the Data Access Layer below (also a bridge), the following is the author summed up 4 big elements:
(1) All data access requests are forwarded through DAF, both
Database is also XML, which guarantees the consistency of data access interfaces;
(2) Treatment of the check and return result of the incoming parameter, all in DAF, which also ensures the consistency of the data format;
(3) All Data Access Operations declared in DAF use Data Entity Façade as a data entity to participate in processing (this is also one of the reasons why Façade), and the Data Access Logic described below does not limit this limit (can be directly Use the frame types such as DataSet / DataTable / ObjectSet as a data entity)!
(4) If you need to perform data exchange or processing via remote access (for example:: Not in Business Logi), you can choose to do in DAF, or in the specific Data Access Logic ( Please refer to the discussion below Data Access Logic).
Speaking here, is everyone that has already impressed DAF?
If it is not very clear, then, the following is the upcoming Data Access logic (please note: Data Access Logic here can also be referred to as DAL, but with Data Access Layer is a very different concept!) Will help you See the true face of Daf
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