失眠网 > PythonC++相互混合调用编程全面实战-17C++调用python函数并传递list参数并获取返回

PythonC++相互混合调用编程全面实战-17C++调用python函数并传递list参数并获取返回

时间：2021-03-17 08:14:36

作者：虚坏叔叔

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C++调用python函数传递list参数并获取返回

一、C++调用python无参数返回值函数

在test.py中添加函数：

print('test.py')def Main():print("Python Main")

在c++中调用这个函数

// C++调用Python函数PyObject* Main = PyObject_GetAttrString(m, "Main");if (Main && PyCallable_Check(Main)) {// 函数对象和参数返回对象if (!PyObject_CallObject(Main, 0)){throw exception("PyObject_CallObject Failed");}}Py_XDECREF(Main);

運行：

可以看到成功調用了。

二、C++调用python带参数和返回值的函数

在test.py中添加函数TestFun：

print('test.py')def Main():print("Python Main")def TestFun(lis):print("In Python", lis)return [1,2,3,4,5,6,7,8,9,10]

在C++中調用

// C++调用Python函数PyObject* Main = PyObject_GetAttrString(m, "Main");if (Main && PyCallable_Check(Main)) {// 函数对象和参数返回对象if (!PyObject_CallObject(Main, 0)){throw exception("PyObject_CallObject Failed");}}Py_XDECREF(Main);// c++调用Python的函数 list参数和list返回值PyObject* TestFun = PyObject_GetAttrString(m, "TestFun");if (TestFun && PyCallable_Check(TestFun)) {// 参数准备参数变量是tuplePyObject *args = PyTuple_New(1); // 参数是元组只有元组这个一个参数// 传递的list对象PyObject *lis = PyList_New(0);for (int i = 0; i < 5; i++)PyList_Append(lis, PyLong_FromLong(i + 100));// 将list写入元组参数列表中PyTuple_SetItem(args, 0, lis);// 函数对象和参数的返回值PyObject* re = PyObject_CallObject(TestFun, args);Py_XDECREF(args); // lis也在args中销毁// 处理返回值if (re){cout << "PyObject_CallObject return" << endl;int size = PyList_Size(re);for (int i = 0; i < size; i++){PyObject *val = PyList_GetItem(re, i);if (!val)continue;printf("[%d]", PyLong_AsLong(val));}Py_XDECREF(re);}}Py_XDECREF(TestFun);

結果

可以看到调用成功了，将传递的列表输出出来，返回值也可以输出出来。

三、完整调用代码贴在下面

#include <iostream>#include <Python.h>#include <exception>using namespace std;int main(int argc, char*argv[]){cout << "C++ call Python" << endl;// 设置Python的Home路径Py_SetPythonHome(L"./");// Python初始化解释器Py_Initialize();PyObject *m = NULL; // 主模块try{int re = 0;// 执行Python脚本re = PyRun_SimpleString("print('Hello world!')");re = PyRun_SimpleString("print(\"__name__ = \", __name__)");// 执行Python文件char* filename = "test.py";FILE * fp = fopen(filename, "r");if (!fp){throw exception("open file failed");}PyRun_AnyFile(fp, filename);if (re != 0){PyErr_Print();throw exception("PyRun_AnyFile failed");}// 获取主模块PyObject *key = PyUnicode_FromString("__main__");m = PyImport_GetModule(key); // 不清理参数，需要手动清理Py_XDECREF(key);// 2-1 调用python的变量 python做配置文件//con = {// "width":1920,// "heigth" : 1080,// "title" : "C++ call Python"//}{// 根据模块和名称获取对象（对象可以是变量、函数和类）PyObject* conf = PyObject_GetAttrString(m, "conf");if (!conf) {throw exception("conf noe find!");}PyObject *key = PyUnicode_FromString("width");int width = PyLong_AsLong(PyDict_GetItem(conf, key));Py_XDECREF(key);key = PyUnicode_FromString("height");int height = PyLong_AsLong(PyDict_GetItem(conf, key));Py_XDECREF(key);key = PyUnicode_FromString("title");wchar_t title[1024] = {0 };int size = PyUnicode_AsWideChar(PyDict_GetItem(conf, key), title, 1023);Py_XDECREF(key);printf("width=%d height=%d \n", width, height);wprintf(L"title=%s\n", title);Py_XDECREF(conf);}{// 获取类PyObject* TypePy = PyObject_GetAttrString(m, "TypePy");if (!TypePy) {throw exception("TypePy noe find!");}// 实例化对象相当于调用构造函数__init__ 传递构造函数的参数NULLPyObject *obj = PyObject_CallObject(TypePy, NULL);if (!obj) {throw exception("obj not Create!");}// 调用类成员函数 i(int) s(string)PyObject *re = PyObject_CallMethod(obj, "test", "is", 2001, "c Para2");cout << "PyObject_CallMethod return" << PyLong_AsLong(re) << endl;Py_XDECREF(re);// 访问成员变量PyObject* var = PyObject_GetAttrString(obj, "id");cout << "TypePy.id=" << PyLong_AsLong(var) << endl;Py_XDECREF(var);Py_XDECREF(obj);Py_XDECREF(TypePy);}{// C++调用Python函数PyObject* Main = PyObject_GetAttrString(m, "Main");if (Main && PyCallable_Check(Main)) {// 函数对象和参数返回对象if (!PyObject_CallObject(Main, 0)){throw exception("PyObject_CallObject Failed");}}Py_XDECREF(Main);// c++调用Python的函数 list参数和list返回值PyObject* TestFun = PyObject_GetAttrString(m, "TestFun");if (TestFun && PyCallable_Check(TestFun)) {// 参数准备参数变量是tuplePyObject *args = PyTuple_New(1); // 参数是元组只有元组这个一个参数// 传递的list对象PyObject *lis = PyList_New(0);for (int i = 0; i < 5; i++)PyList_Append(lis, PyLong_FromLong(i + 100));// 将list写入元组参数列表中PyTuple_SetItem(args, 0, lis);// 函数对象和参数的返回值PyObject* re = PyObject_CallObject(TestFun, args);Py_XDECREF(args); // lis也在args中销毁// 处理返回值if (re){cout << "PyObject_CallObject return" << endl;int size = PyList_Size(re);for (int i = 0; i < size; i++){PyObject *val = PyList_GetItem(re, i);if (!val)continue;printf("[%d]", PyLong_AsLong(val));}Py_XDECREF(re);}}Py_XDECREF(TestFun);}Py_XDECREF(m);// 清理pythonPy_Finalize();}catch (const std::exception&ex){if (PyErr_Occurred())PyErr_Print();cout << ex.what() << endl;// 清理pythonPy_XDECREF(m);Py_Finalize();}getchar();return 0;}

四、总结

本文使用C++调用python函数传递list参数并获取返回。如果觉得文章对你有用处，记得点赞收藏转发一波哦，博主也支持为铁粉丝制作专属动态壁纸哦~

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