【C++/Python编程】c++调用python

参考：https://docs.python.org/3/c-api

https://blog.youkuaiyun.com/lingtianyulong/article/details/81146495

基础vs2015导入python包直接略过直接上代码：

c++代码：main.cpp

#include <Python.h>
#include <iostream>
#include <string>
using namespace std;

int main(int argc, char* argv[])

{
	//初始化python
	Py_Initialize();

	PyRun_SimpleString("import sys");
	//此处不能设置当前main函数的同级目录
	PyRun_SimpleString("sys.path.append('C:/Users/Administrator/Desktop')");
	//定义python类型的变量
	PyObject *pModule = NULL;
	PyObject *pFunc = NULL;
	PyObject *pArg = NULL;
	PyObject *result = NULL;
	PyObject *pClass = NULL;
	PyObject *pInstance = NULL;
	PyObject *pDict = NULL;
	//直接运行python代码
	PyRun_SimpleString("print('python start')");
	//引入模块
	pModule = PyImport_ImportModule("mytest2");
	//cout << "pModule:" << pModule << endl;
	if (!pModule)
	{
		cout << "Import Module Failed" << endl;
		//system("pause");
		return 0;
	}


	//获取模块字典属性
	pDict = PyModule_GetDict(pModule);

	直接获取模块中的函数
	pFunc = PyObject_GetAttrString(pModule, "hello");

	//参数类型转换，传递一个字符串。将c/c++类型的字符串转换为python类型，元组中的python类型查看python文档
	pArg = Py_BuildValue("(s)", "hello charity");
	// 调用直接获得的函数,并传递参数
	PyEval_CallObject(pFunc, pArg);

	//system("pause");
	// 第二种方式从字典属性中获取函数
	pFunc = PyDict_GetItemString(pDict, "arg");
	// 参数类型转换,传递两个整型参数
	pArg = Py_BuildValue("(i, i)", 1, 2);
	// 调用函数,并得到 python 类型的返回值
	result = PyEval_CallObject(pFunc, pArg);//注意：所有返回值都用PyObject指针对象接收
	// c 用来保存 C/C++ 类型的返回值
	int c = 0;
	// 将 python 类型的返回值转换为 C/C++类型
	PyArg_Parse(result, "i", &c);//对python返回值进行解析
	cout << "a+b = " << c << endl;

	// 通过字典属性获取模块中的类 
	pClass = PyDict_GetItemString(pDict, "Test");

	if (!pClass)
	{
		cout << "获取模块中的类失败" << endl;
		//system("pause");
		return 0;
	}

	// 实例化获取的类
	pInstance = PyInstanceMethod_New(pClass);

	//调用类的方法并传参
	result = PyObject_CallMethod(pInstance, "say_hello", "(s,s)", "", "charity");

	//输出返回值
	char* name = NULL;
	PyArg_Parse(result, "s", &name); 

	printf("%s\n", name);

	PyRun_SimpleString("print('python end')");

	释放python

	Py_Finalize();

	system("pause");

	return 0;

}

python代码：mytest2.py

def hello(s):
    #print("hello world")
    print(s)
 
 
def arg(a, b):
    #print('a=', a)
    #print('b=', b)
    return a + b
 
 
class Test:
    def __init__(self):
        print("init")
 
    def say_hello(self, name):
        #print("hello", name)
        return name

运行结果：