Python 将std::string传递给PyObject\u CallFunction
当我运行Python 将std::string传递给PyObject\u CallFunction,python,c++,python-embedding,Python,C++,Python Embedding,当我运行pResult=PyObject\u CallFunction(pFunc,“s”和“String”)时,python脚本返回正确的字符串。但是,如果我尝试运行此命令: std::string passedString = "String"; pResult = PyObject_CallFunction(pFunc, "s", &passedString) 然后将预设值转换为std::string,打印时得到。下面是一些(可能)返回的完整代码: C++代码: #include
pResult=PyObject\u CallFunction(pFunc,“s”和“String”)
时,python脚本返回正确的字符串。但是,如果我尝试运行此命令:
std::string passedString = "String";
pResult = PyObject_CallFunction(pFunc, "s", &passedString)
然后将预设值转换为std::string
,打印时得到
。下面是一些(可能)返回
的完整代码:
C++代码:
#include <Python.h>
#include <string>
#include <iostream>
int main()
{
PyObject *pName, *pModule, *pDict, *pFunc;
// Set PYTHONPATH TO working directory
setenv("PYTHONPATH",".",1); //This doesn't help
setenv("PYTHONDONTWRITEBYTECODE", " ", 1);
// Initialize the Python Interpreter
Py_Initialize();
// Build the name object
pName = PyUnicode_FromString((char*)"string");
// Load the module object
pModule = PyImport_Import(pName);
// pDict is a borrowed reference
pDict = PyModule_GetDict(pModule);
// pFunc is also a borrowed reference
pFunc = PyDict_GetItemString(pDict, (char*)"getString");
if (pFunc != NULL)
{
if (PyCallable_Check(pFunc))
{
PyObject *pResult;
std::string passedString = "String";
pResult = PyObject_CallFunction(pFunc, "s", &passedString);
PyObject* pResultStr = PyObject_Repr(pResult);
std::string returnedString = PyUnicode_AsUTF8(pResultStr);
std::cout << returnedString << std::endl;
Py_DECREF(pResult);
Py_DECREF(pResultStr);
}
else {PyErr_Print();}
}
else {std::cout << "pFunc is NULL!" << std::endl;}
// Clean up
Py_DECREF(pFunc);
Py_DECREF(pDict);
Py_DECREF(pModule);
Py_DECREF(pName);
// Finish the Python Interpreter
Py_Finalize();
}
我使用的是Ubuntu(linux),我使用的是Python 3.4,您应该向
PyObject\u CallFunction
传递一个c风格的字符串,以便代码正常工作。要从std::string
获取c字符串,请使用c_str()
方法。因此,下面这句话:
pResult = PyObject_CallFunction(pFunc, "s", &passedString);
应该是这样的:
pResult = PyObject_CallFunction(pFunc, "s", passedString.c_str());
我试过了,我得到了一个错误:
error:lvalue required作为一元操作数
Oops,我错了,我在passedString.c_str()之前使用了&
,你需要传递一个char*
,所以不需要&
pResult = PyObject_CallFunction(pFunc, "s", passedString.c_str());