Why cannot I call non-static members (attributes) in the static method (function) of a class )?

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The program will eventually be executed in the memory, and variables can be accessed only when they have a place in the memory.

Static members of a class (variables and methods) belong to the class itself. When the class is loaded, the memory is allocated and can be directly accessed through the class name. Non-static members (variables and methods) it is a class object, so the memory is allocated only when the class object is generated (the instance of the class is created) and then accessed through the Class Object (instance.

An error occurs when a static member of a class accesses its non-static member because the static member of the class already exists when the non-static member of the class does not exist, an error occurs when accessing something that does not exist in the memory:

Class ca {
PRIVATE:
Int A; // non-static member. Memory is allocated when a class instance is created. different instances of the class correspond to different memory regions.
Static int B; // static member. Memory is allocated when the class is loaded. all instances of the class are shared.

Public:
Void FA (void ){
A = 1;
B = 1;
}

Static void FB (void ){
// A = 1; // non-static member can't be accessed by static function
B = 1;
}
};
/**
* Static member must be initialized before using ,.
* Or error: unresolved external symbol "Private: static int CA: B"
*/
Int CA: B = 1;

Int main (void ){

CA;
CA. FA ();

CA: FB ();

Return 0;
}

This article from the csdn blog, reproduced please indicate the source: http://blog.csdn.net/ZOLoveGD/archive/2008/09/14/2914559.aspx