cstring---->char *(Unicode字符集)

CString str;
const size_t strsize = (str.GetLength() + 1) * 2;
char *c= new char[strsize];
size_t sz = 0;
wcstombs_s(&sz, c, strsize, str, _TRUNCATE);

参考地址：https://blog.csdn.net/qq_23494915/article/details/78732581