c/c++再學習：C與Python相互調用

時間 2019-12-05

標籤 c++ 學習 python 相互調用欄目 C&C++ 简体版

原文原文鏈接

c/c++再學習：Python調用C函數

Python 調用C函數比較簡單
這裏兩個例子，一個是直接調用參數，另外一個是調用結構體
C代碼python

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代碼c++

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 = 10
coredata.i2 = 20
coredata.str = b"hello world"
coredata_ptr = byref(coredata)
struct_add_val = core.struct_add(coredata_ptr)

print(struct_add_val)

結果windows

3
6
30
hello world

C調用python函數

c調用python，須要在增長<Python.h>和python36.lib，有時遇到編譯時須要python36_d.lib時，只須要將python36.lib複製重命名爲python36_d.lib放在同目錄下便可函數

python代碼學習

def py_print():
    print("py_print")

def py_add(a,b):
    return a+b

c代碼ui

#include "stdio.h"
#include "windows.h"
#include <Python.h>   

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;
}

結果code