c/c++再学习：Python调用C函数

Python 调用C函数比较简单

这里两个例子，一个是直接调用参数，另一个是调用结构体

C代码

typedef struct {    int i1;    int i2;    char str[20];} core_data_t;__declspec(dllexport) int add(int a, int b){    return a + b;}__declspec(dllexport) int multi(int a, int b){    return a * b;}__declspec(dllexport) int struct_add(core_data_t* data){    printf("%s\n", data->str);    return data->i1 + data->i2;}

python代码

from ctypes import *core = CDLL('core.dll')add_val = core.add(1, 2)multi_val = core.multi(2, 3)print(add_val)print(multi_val)class CoreData(Structure):    _fields_ = [("i1", c_int),                ("i2", c_int),                ("str", c_char*20)]coredata = CoreData()coredata.i1 = 10coredata.i2 = 20coredata.str = b"hello world"coredata_ptr = byref(coredata)struct_add_val = core.struct_add(coredata_ptr)print(struct_add_val)

结果

3630hello world

C调用python函数

c调用python，需要在增加<Python.h>和python36.lib，有时遇到编译时需要python36_d.lib时，只需要将python36.lib复制重命名为python36_d.lib放在同目录下即可

python代码

def py_print():    print("py_print")def py_add(a,b):    return a+b

c代码

#include "stdio.h"#include "windows.h"#include 
    
        void main(){    Py_Initialize();                      PyObject* pModule = NULL;            PyObject* pFunc = NULL;            PyObject* pArgs = NULL;    PyObject* pValue = NULL;    pModule = PyImport_ImportModule("python_demo");              pFunc = PyObject_GetAttrString(pModule, "py_print");       PyEval_CallObject(pFunc, NULL);       pFunc = PyObject_GetAttrString(pModule, "py_add");    pArgs = PyTuple_New(2);    PyTuple_SetItem(pArgs, 0, Py_BuildValue("i", 5));    PyTuple_SetItem(pArgs, 1, Py_BuildValue("i", 10));    pValue = PyEval_CallObject(pFunc, pArgs);    int res = 0;    PyArg_Parse(pValue, "i", &res);    printf("res %d\n", res);    Py_Finalize();       return;}
    

结果

py_printres 15