python匯出函數方法__函數

1、匯出函數範例

#include <python/Python.h>#include <iostream>using namespace std;int add(int arg1, int arg2){return arg1 + arg2;}int sub(int arg1, int arg2){return arg1 - arg2;}static PyObject* math_add(PyObject* self, PyObject* args){int arg1, arg2;if (!PyArg_ParseTuple(args, "ii", &arg1, &arg2)){return NULL;}int result = add(arg1, arg2);return (PyObject*)Py_BuildValue("i", result);}static PyObject* math_sub(PyObject* self, PyObject* args){int arg1, arg2;if (!PyArg_ParseTuple(args, "ii", &arg1, &arg2)){return NULL;}int result = sub(arg1, arg2);return (PyObject*)Py_BuildValue("i", result);}static PyMethodDef MathMethods[] ={{ "add", math_add, METH_VARARGS, "Execute math command:add." },{ "sub", math_sub, METH_VARARGS, "Execute math command:sub." },{ NULL, NULL }};static struct PyModuleDef MathModule ={PyModuleDef_HEAD_INIT,"math_capi","example module doc string",-1,MathMethods,NULL,NULL,NULL,NULL};static PyObject* __mathError;PyMODINIT_FUNCPyInit_Math(){PyObject* module = PyModule_Create(&MathModule);if (NULL == module){return NULL;}__mathError = PyErr_NewException("math.error", NULL, NULL);Py_INCREF(__mathError);PyModule_AddObject(module, "error", __mathError);return module;}std::string format_python_traceback(PyObject *tb){PyTracebackObject *trace = (PyTracebackObject*)tb;std::string stack;stack = "Traceback:\n";while (trace && trace->tb_frame){/*PyFrameObject *frame = (PyFrameObject*)trace->tb_frame;stack += base::strfmt("  File \"%s\", line %i, in %s\n",PyString_AsString(frame->f_code->co_filename),trace->tb_lineno,PyString_AsString(frame->f_code->co_name));PyObject *code = PyErr_ProgramText(PyString_AsString(frame->f_code->co_filename), trace->tb_lineno);if (code){stack += base::strfmt("    %s", PyString_AsString(code));Py_DECREF(code);}*/trace = trace->tb_next;}return stack;}std::string format_python_exception(std::string &summary){std::string reason, stack;PyObject *exc, *val, *tb;PyErr_Fetch(&exc, &val, &tb);PyErr_NormalizeException(&exc, &val, &tb);if (val){PyObject *tmp = PyObject_Str(val);if (tmp){reason = PyBytes_AsString(tmp);Py_DECREF(tmp);}}if (tb)    stack = format_python_traceback(tb);elsestack = "No stack information. ";PyErr_Restore(exc, val, tb);summary = reason;return stack + reason+"\n";}static std::string exception_detail(){PyObject *exc_class = NULL, *exc = NULL, *exc_tb = NULL;PyErr_Fetch(&exc_class, &exc, &exc_tb);if (exc){PyObject *str = PyObject_Str(exc);if (str){//char *s = PyByteArray_AsString(str);char *s = PyBytes_AsString(str);if (s)return s;Py_DECREF(str);}Py_DECREF(exc);}Py_XDECREF(exc_class);Py_XDECREF(exc_tb);// PyErr_Restore(exc, val, tb);return "";}// 調用輸出"Hello World"函數voidHelloWorld(){PyImport_AppendInittab("math_capi", PyInit_Math);Py_Initialize();PyImport_ImportModule("math_capi");PyRun_SimpleString("import sys");PyRun_SimpleString("sys.path.append('.')");PyRun_SimpleString("sys.path.append('./')");PyRun_SimpleString("print 'Hello Python!'\n");PyObject* pModule = PyImport_ImportModule("testpython");PyErr_Print();std::string strError = exception_detail();if (!pModule){return;}PyErr_Print();PyObject* pFunc = PyObject_GetAttrString(pModule, "HelloWorld");PyErr_Print();if (pFunc && PyCallable_Check(pFunc)){PyObject_CallObject(pFunc, NULL);}Py_Finalize();}// 調用Add函數,傳兩個int型參數voidAdd(){Py_Initialize();PyObject* pModule = NULL;PyObject* pFunc = NULL;pModule = PyImport_ImportModule("testpython");    // Test:Python檔案名稱pFunc = PyObject_GetAttrString(pModule, "add");   // Add:Python檔案中的函數名// 建立參數PyObject* pArgs = PyTuple_New(2);                 // 函數調用的參數傳遞均是以元組的形式打包的,2表示參數個數PyTuple_SetItem(pArgs, 0, Py_BuildValue("i", 5)); // 0---序號  i表示建立int型變數 PyTuple_SetItem(pArgs, 1, Py_BuildValue("i", 7)); // 1---序號// 傳回值PyObject* pReturn = NULL;pReturn = PyEval_CallObject(pFunc, pArgs);        // 調用函數// 將傳回值轉換為int類型.int result;PyArg_Parse(pReturn, "i", &result);               // i表示轉換成int型變數cout << "5+7 = " << result << endl;Py_Finalize(); }// 參數傳遞的類型為字典void TestTransferDict(){Py_Initialize();PyObject* pModule = NULL;PyObject* pFunc = NULL;pModule = PyImport_ImportModule("testpython");                      // Test:Python檔案名稱pFunc = PyObject_GetAttrString(pModule, "TestDict");                // Add:Python檔案中的函數名// 建立參數PyObject* pArgs = PyTuple_New(1); PyObject* pDict = PyDict_New();                                     // 建立字典類型變數PyDict_SetItemString(pDict, "Name", Py_BuildValue("s", "scott"));   // 往字典類型變數中填充資料PyDict_SetItemString(pDict, "Age", Py_BuildValue("i", 18));         // 往字典類型變數中填充資料PyTuple_SetItem(pArgs, 0, pDict);                                   // 0---序號  將字典類型變數添加到參數元組中// 傳回值PyObject* pReturn = NULL; pReturn = PyEval_CallObject(pFunc, pArgs);                          // 調用函數// 處理傳回值int size = PyDict_Size(pReturn);cout << "返回字典的大小為: " << size << endl;PyObject *pNewAge = PyDict_GetItemString(pReturn, "Age");int newAge;PyArg_Parse(pNewAge, "i", &newAge);cout << "True Age: " << newAge << endl;Py_Finalize();}// 測試類別   voidTestClass(){Py_Initialize();PyObject* pModule = NULL;PyObject* pFunc = NULL;pModule = PyImport_ImportModule("testpython");                        // Test:Python檔案名稱pFunc = PyObject_GetAttrString(pModule, "TestDict");                  // Add:Python檔案中的函數名// 擷取Person類PyObject* pClassPerson = PyObject_GetAttrString(pModule, "Person");// 建立Person類的執行個體PyInstance_NewPyObject* pInstancePerson = PyObject_CallObject(pClassPerson,NULL);// 調用方法PyObject_CallMethod(pInstancePerson, "greet", "s", "Hello Kitty");    // s表示傳遞的是字串,值為"Hello Kitty" Py_Finalize();}int main(int argc, char *argv[])   {/* 傳遞argv[0]給Python解譯器*/  //Py_SetProgramName(argv[0]);   cout << "Starting Test..." << endl;cout << "HelloWorld()-------------" << endl;HelloWorld();cout << "Add()--------------------" << endl;         Add();cout << "TestDict-----------------" << endl;TestTransferDict();cout << "TestClass----------------" << endl;TestClass();system("pause");return 0;}  

2、編寫指令碼

#testpython.py
import math_capi
def HelloWorld():
    print("Hello World!")
    print(math_capi.add(3,5))
    print(math_capi.sub(5,3))
def add(a, b):
    return a+b
def TestDict(dict):
    print(dict)   
    dict["Age"] = 17
    return dict
class Person:
    def greet(self, greetStr):
        print(greetStr)
#print add(5,7) 
#a = raw_input("Enter To Continue...")