关键词calss(类)与struct作用相近,但缺省关键词不同
类class(缺省类型为private)
struct (缺省类型为public)
句柄 类(handle class)的作用:便于修改一个类,减少重复编译
//例子中,头文件中只包含公共接口和一个简单的未完全指定的类指针
//:HANDLE.H--Handle classes #ifndef HANDLE_H_ #define HANDLE_H_ class handle{ struct cheshire; cheshire* smile; public: void initialize(); void cleanup(); int read(); void change(int); }; #enddef //:HANDLE.CPP-Handle implementation #include"handle.h" #include<stdlib.h> #include<assert.h> //define handle's implementation struct handle::cheshire{ //对类指针按照需求进行定义 int i; }; void handle::initialize(){ smile=(cheshire*)malloc(sizeof(cheshire)); assert(smile); smile->i=0; } void handle::cleanup(){ free(smile); } int handle::read(){ return smile->i; } void handle::change(int x){ smile->i=x; } //:USEHANDLE.CPP--use the handle class #include<handle.cpp> main(){ handle u; u.initialize(); u.read(); u.change(1); u.cleanup(); }