member

问题 I try to get the address of some struct member in array of structures but i don't want to use name of that member. It should be something like this: typedef struct{ unsigned char MrChar; unsigned short MrShort; unsigned long MrLong; unsigned char MrArray[5]; }tModule; static tModule taModulesArray[MODULES_AMOUNT] = { // MODULES_AMOUNT = 2 {0x22, 0x3298, 0x92324583, "djsoe"}, // Module 1 {0x33, 0x1843, 0x65644113, "gskwc"}, // Module 2 }; unsigned long usGetMemberAddr(unsigned long ulModule,

问题 OK, I've been through all of the threads that supposedly deal with this problem and none of them seem to rectify my issue. Basically I have a tableview setup with core data and when I segue into the next view controller I want to pass some data. As you know the data being passed must already be declared in the destination view controller, which it is. But I keep getting an error saying the ViewController does not have a member name nItem (the variable I am passing). Here is the section of

问题 SingleMonitorInfo::SingleMonitorInfo(MONITORINFOEX* lpMONITORINFOEX) :rcMonitorArea(lpMONITORINFOEX->rcMonitor), rcWorkArea(lpMONITORINFOEX->rcWork), dwStatusFlags(lpMONITORINFOEX->dwFlags), szDeviceName({ '\0' }), szMonitorName({ '\0' }), szMonitorDescription({ '\0' }), lpPixelArray(NULL) { wcscpy_s(SingleMonitorInfo::szDeviceName, 33, lpMONITORINFOEX->szDevice); SingleMonitorInfo::setStringMonitorNameAndDescription(lpMONITORINFOEX->szDevice); } I am rewriting my program using member

问题 I have a map of pointer to member declared as : std::map<char, T (Operand::*)(const T &, const T &)> op_map; I fill my map with pointer to member directly in the constructor of my class with : op_map['+'] = &Operand::op_add; For example, op_add source code is : T op_add(const T & a, const T & b) { return a + b; } And I want to call my pointer to member from a const function. Here is the source code : IOperand *res_int32(char op, const IOperand & rhs) const { IOperand *res = const_cast

问题 I'm trying to use this function, but I cannot find any examples. So I tried every possible way that I can think of, and each time I get a different error : cv::Mat salMap; cv::saliency::StaticSaliencySpectralResidual::computeSaliency(img, salMap); this causes in error : 'cv::saliency::Saliency::computeSaliency': illegal call of non-static member function Then I tried to instantiate the class like this : cv::saliency::StaticSaliencySpectralResidual myObj; myObj.computeSaliency(grayImg, salMap)

问题 I'm writing a class to access global variables through string-input (serial, webinterface, telnet, etc.) on an esp32. Therefore my variableAccess class has an attribute representing the variables address and an enum specifying the datatype (to make it short only int and float are in the example code below). The variable can then be set/read by the setValue/readValue methods. During initialization the variableAccess objects are created and stored in a vector 'allVariables' Now for my problem:

问题 #include <iostream> class FooParent { public: FooParent(int* new_p_bar) { p_bar = new_p_bar; } public: int* p_bar; }; class FooChild : public FooParent { public: int bar; public: FooChild(int new_x) :FooParent(&bar) ,bar(new_x) \\ point of concern {} }; int main() { FooChild foo(8); std::cout << foo.bar << std::endl; } The above example works as I want it to .i.e. link the pointer p_bar to bar . However, my concern is that I am pointing to a member whose constructor is not yet called. Is this

问题 Let's say, I have an array of complex data type objects. For example: FullName[100] . Each FullName object has has 2 class member variables: String FirstName and String LastName . Now, from this array of FullName objects, I want to retrieve an array of String FirstNames[] . How can I do this without the extensive for loop application? 回答1: You can try to take a look at Functional Programming in Java and apply map function from one of the libraries. 回答2: I'm not sure why avoiding a loop is so

问题 This question already has answers here : Can't access derived class method from pointer of type base class (3 answers) Closed 5 years ago . I am trying to access derived class' private members via an object of the base class. Here is what I'm trying to do : class A { private: int a, b; public: A(_a, _b) : a(_a), b(_b) {} int getA() { return a; } int getB() { return b; } }; class B : public A { private: int c; public: B(_a, _b, _c) : A(_a, _b), c(_c) {} int getC() { return c; } }; vector<A*>

问题 Issue about Storeing unknown Data in a Class How can I provide a class in C++ which is able to store any number of variables each of any type? From inside and outside of the class I would like to read, add, modify and delete these data. So what I am looking for is maybe a list where the datatypes can vary. Example how the Usage could look like Class Object(); Object->Storage->Create("position", "float"); // create Object->Storage->Write("position", 42.0f); // write int Result = Object-