Multiple inheritance is generally discouraged, but why is it used a lot in COM?

galanodel

Why not use object composition?

doubt

food0012

Multiple inheritance that is not advocated generally refers to multiple inheritance implementation classes, and multiple inheritance of abstract classes (interfaces) is good. Object composition can replace inheritance, but it increases the amount of code, and there is nothing if inheritance does not cause any problems. Advantage

bobbykds1221

People who don't use C ++ don't advocate using multiple inheritance!

goodjianli

I think this may be a problem of understanding: generally we say multiple inheritance, often referring to the realization of inheritance, this multiple inheritance is not advocated.
The multiple inheritance used in COM actually refers to interface inheritance, that is: functional inheritance
We often say that targeting an interface rather than implementing programming is reflected here. By inheriting the interface, the data and methods are separated, and at the same time,
The same calling method of the same type of class is reached (that is, the subclass can be called through the parent class)

In fact, this method is the same as the interface in Java, except that C ++ (or COM) is implemented by abstracting the parent class.

sheep0214

I do n’t encourage the use of multiple inheritance. I suggest that the host can see the source code of wtl, maybe it will be very inspiring.