可以在C ++ Header.h文件中放置非（静态常量整型）类型

// MyClass.h
#ifndef __MY_CLASS_H__
#define __MY_CLASS_H__

#include <string>

class MyClass
{
    static const std::string MyStaticConstString; // I cannot initialize it here, because it\'s not an integral type.
};

// OK, let\'s define/initialize it out side of the class declaration
// static
const std::string MyClass::MyStaticConstString = \"Value of MyStaticConstString\";

#endif

MyClass

__MY_CLASS_H__

//myclass.h

 // MyClass.h
 #ifndef MY_CLASS_H
 #define MY_CLASS_H

class MyClass
{
    static const std::string MyStaticConstString; // I cannot initialize it here, because it\'s not an integral type.
};

extern std::string some_global_variable; //declare this with extern keyword

 #endif //MY_CLASS_H

//myclass.cpp
#include \"myclass.h\"

const std::string MyClass::MyStaticConstString = \"Value of MyStaticConstString\";

std::string some_global_variable = \"initialization\";

MY_CLASS_H