我有一个 C++ 类，它通过 boost python 框架暴露给 python。

    struct Var 
    { 
        Var(std::string name) : name(name), value() {} 
        std::string const name; 
        float value; 
    }; 
 
    BOOST_PYTHON_MODULE(hello) 
    { 
      class_<Var>("Var", init<std::string>()) 
        .def_readonly("name", &Var::name) 
        .def_readwrite("value", &Var::value); 
       ; 
    } 

下面是使用此类的Python脚本:

x = hello.Var("hello") 
def print_func(): 
    print(x.value) 

是否可以访问对象x在 C++ 代码中并分配 value成员变量 C++ 中的值，当 print_func() 时打印在python脚本中执行？

请您参考如下方法:

您可以更改 python 和 c++ 代码，如下所示

//I hope you are expecting some functionality like below 
 
class Var 
{ 
    public: 
        Var(std::string name) : name(name), value() {} 
        std::string const name; 
        double value; 
        void set_value(); 
        double get_value(); 
}; 
 
Var::set_value(double value) 
{ 
    this->value = value; 
} 
 
double Var::get_value(){ 
 
    return this->value; 
} 
 
// c++ Var class constructor caller  
Var* var_constructor_caller(string name){ 
 
    return new Var(name); 
} 
 
BOOST_PYTHON_MODULE(hello_ext) 
{ 
    //class_<Var>("Var", init<std::string>()) 
    class_<Valr>("Var") // this line is for c++ class not exposed to python 
        .def("set_value", &Var::set_value) 
        .def("get_value", &Var::get_value) 
        .def_readonly("name", &Var::name) 
        .def_readwrite("value", &Var::value); 
    ; 
 
    def("var_constructor_caller", var_constructor_caller, return_value_policy<manage_new_object>()); 
    // by <manage_new_object> return type you are giving owner ship to python to delete the object 
} 

下面是使用此类的Python脚本:

import hello_ext as hello 
    var_obj = hello.var_constructor_caller("myname") 
    var_obj.set_value(3.14) 
    value = var_obj.get_value() 
    print value  
    var_object.value = 5.75 #you call directly assign value also to c++ class data member  
    print value