When to write the function, when to write the class.

The duplicated code is written as a separate function, and if there are many repeated sequential function calls, it is organized into a function. If these functions have common data, they can be organized into a class. (Actually the data is the soul, the function itself is empty, is the appearance, the external interface and the Service tool.) Calling WINAPI appears to be able to implement certain functions immediately, and in fact the function modifies the internal data of the OS to achieve the corresponding function .

In other words, if there is no duplicate code and no duplicate function calls, then the 5000 lines of code are likely to be written together!

When to write the function, when to write the class.