为什么所有对象的类的静态成员都相同？

Question

为什么我们不为不同的对象提供不同的静态变量副本？

Answer 1

Because they would be instance members then.

The primary characteristic of static members is that they're shared by all the instances of the class.

Answer 2

Because the section $9.4.2/1 from the C++ Standard (2003) says,

A static data member is not part of the subobjects of a class. There is only one copy of a static data member shared by all the objects of the class.

Since the Standard alone decides what C++ is, what not, so it's how C++ has been designed!

Static members are more like global objects. The same copy belong to all objects!

See this post for detail answer : Do static members of a class occupy memory if no object of that class is created?

Answer 3

A static member is not associated with a specific instance.

If you want different values of the member for each instance you should use instance members (remove the static keyword).

Answer 4

It's by definition- a static object is one that's shared by all instances of the class. Regular members don't have this property.

Answer 5

That is the definition of static - one copy of the data exists. It is separately stored, most likely along with all the other static data of the library or application.

Answer 6

因为这就是static意味着在这种情况下。

Answer 7

因为类静态成员分别存储在BSS部分中，所以类的每个实例都具有相同的值。