环境

C++ 14，Python 3.1 ，使用CMake构建

CMakeLists.txt:

cmake_minimum_required(VERSION 3.22)
project(pythonTest)
# Python环境配置
find_package(Python3 COMPONENTS Interpreter Development REQUIRED)
include_directories(${PYTHON_INCLUDE_DIR})

set(CMAKE_CXX_STANDARD 14)
add_executable(pythonTest main.cpp)

# 不加会导致运行时找不到定义
target_include_directories(${PROJECT_NAME} PRIVATE ${Python3_INCLUDE_DIRS})
target_link_libraries(${PROJECT_NAME} ${Python3_LIBRARIES})

调用

main.cpp

#include <iostream>
#include <Python.h>

int main() {
    //初始化Python环境
    Py_Initialize();
    std::string result;
    //追加python文件路径至Python环境
    PyObject *sysPath = PySys_GetObject("path");
    PyList_Append(sysPath, PyUnicode_FromString("D:/"));
    //导入Python文件
    PyObject *pModule = PyImport_ImportModule("c_plus_test");
    if (pModule != NULL) {
        //获取函数
        PyObject *pFunc = PyObject_GetAttrString(pModule, "call_python");
        if (pFunc != NULL) {
            PyObject *myResult = PyObject_CallObject(pFunc, NULL);
            //转换结果至c++字符串
            result = PyUnicode_AsUTF8(myResult);
            Py_DECREF(myResult);
        } else {
            std::cout << "call python function fail!!!!" << std::endl;
        }
        Py_DECREF(pFunc);
    } else {
        std::cout << "import module fail!!!!" << std::endl;
    }
    std::cout << "get python reault:" << result << std::endl;
    //释放资源
    Py_DECREF(sysPath);
    Py_DECREF(pModule);
    Py_Finalize();
    return 0;
}

Python3中去掉了PyString_AsString使用PyUnicode_AsUTF8转换字符串

c_plus_test.py

import os

def call_python():
    helloStr = "Hello in Python";
    print('Hello in Python');
    return helloStr;

参考资料

https://zhuanlan.zhihu.com/p/149887203

https://blog.csdn.net/iamqianrenzhan/article/details/86516440