c调用c++对象中的方法

普通调用

https://www.cnblogs.com/Yogurshine/p/3913073.html

https://zhidao.baidu.com/question/531286375.html

这个问题很有意思&＃xff0c;我之前还没碰到过呢&＃xff0c;我帮你在全球最大的编程论坛stackoverflow上搜了一个答案&＃xff1a;
这个答案大意是说&＃xff0c;C语言没有this指针&＃xff0c;所以要自己写一个wrap API来封装C&＃43;&＃43;的对象。
这个论坛高手云集&＃xff0c;包括很多业界大拿&＃xff0c;所以这个答案还是很可信的。下面的api.h 就是你要写的wrap API

C has no thiscall notion. The C calling convention doesn&＃39;t allow directly calling C&＃43;&＃43; object member functions.
Therefor, you need to supply a wrapper API around your C&＃43;&＃43; object, one that takes the this pointer explicitly, instead of implicitly.
Example:

// C.hpp
// uses C&＃43;&＃43; calling convention
class C {
public:
bool foo( int arg );
};

C wrapper API:

// api.h
// uses C calling convention
#ifdef __cplusplus
extern "C" {
#endif

void* C_Create();
void C_Destroy( void* thisC );
bool C_foo( void* thisC, int arg );

#ifdef __cplusplus
}
#endif

Your API would be implemented in C&＃43;&＃43;:

#include "api.h"
#include "C.hpp"

void* C_Create() { return new C(); }
void C_Destroy( void* thisC ) {
delete static_cast(thisC);
}
bool C_foo( void* thisC, int arg ) {
return static_cast(thisC)->foo( arg );
}