I met the problem again.
In my program:
#define DllExport __declspec(dllexport)
/* Declare function */
extern "C" DllExport int fun1(int p1);
/* Function body */
extern "C" DllExport int fun1(int p1)
But in that two line about function header, it said
... error C2059: syntax error : 'string'
But in that two line, I don't write the token 'string'
So what happen? Is there any limit for that use?