Click on the form of each column title can achieve sorting (from big to small, from small to large)
1, process-oriented manner
2, the object-oriented implementation
Command's angle to consider what they have to function in this class, after class package in which you can directly call
And then go write function of the specific implementation (process-oriented)
--- understood that encapsulation of object-oriented process is highly oriented, not a replacement.
Question: What are the objects, members of the object (to around specific functions)
Left: process-oriented right: Object-Oriented
Precautions: different positions of this point, by the following general this variable stores the current