I've written a simple class given below. I had set the values through setab() function but the add()function didn't work.
Compiler shows CPP/class.cpp|20|error: ‘int Calc::add()’ is private|
#include <iostream>
using namespace std;
class Calc
[Code]....
Am trying to write table object into file. Here's the source code
.hpp file
class Table {
private:
int table_no;
std::string table_type;
bool engaged;
std::time_t start_time;
double total_sec;
[Code] ....
When i compile the above code i get the following error...
table.hpp: In function ‘std::ifstream& operator>>(std::ifstream&, Table&)’:
table.hpp:19:7: error: ‘int Table::table_no’ is private
table.cpp:91:12: error: within this context
table.hpp:20:15: error: ‘std::string Table::table_type’ is private
table.cpp:92:12: error: within this context ...........
if we don't provide the acces modifiers for base class and we need to manipulate the private data of base class in derived class. Is there anyway to acces the private data members? Here's a coding example
class A {
private :
int a;
};
class B : public class A {
public :
void displayA() { cout<<a<<endl; }
};
how i can acces the a of base class A in derived class B without acces modifiers.
This question is more from a design point-of-view rather than coding it to be a fully functional.
So here it goes:
I have multiple files which each require their own object of same class type (ref. First Class). File contents are read from a file to a unordered_map<std::string, std::vector<std::string>> which is either private or protected member inside First Class. First Class does not need any public functions to add, remove or change the data during runtime, but changes are only being made by checking if the file size has changed during the day, if the size is not equal to the last check, map gets updated.
Now, I have a Second Class which is a data handler class. It has public member functions with arguments that needs to be get from First Class's unordered_map using const_iterator. Which way to go with design and implementation.
I know there's two methods to do this. Re-doing handler class is also not out of the question. These two methods I'm aware of are:
1. Declare these maps to local scope, build few global functions and here we go. (Probably the easiest way.)
2. Create public member functions to a First Class which either return a pointer or a reference to a protected/private member. (I'm under the impression that I really shouldn't be doing this because of a bad coding practice.)
Note that I don't need any code here, just some other point-of-views regarding the subject itself for learning better coding practices.
I've created a class called Voter with a private member variable ID, also I have a variable in my main function to be ID as well. I'm trying to compare the two ID's but when I do so:
if (ID == V.ID)
I get the error - 'std::string Voter::ID' is private within this context.
I know that because it's private I can't access it, but how do I?
How does an object access its private data members in copy constructor.
The relevant part of the code: Code: C::C(const C &obj)
{
x = obj.x;
y = obj.y;
}
Normally the object1 called "obj" cannot access its private data members outside. But in this situation it can access. How can it be explained?
Here are the complete code:
Code:
#include <iostream>
using namespace std;
class C{
public:
C(int,int);
C(const C &);
[Code] .....
I have a method:
int filetodb(std::wstring szwf, SQLHANDLESTR *h);
I want to use it, in a thread.
std says, use thread, as:
std::thread second (bar,0); // spawn new thread that calls bar(0)
How can I do this, for my method, that uses more than one, i.e., two, parameters?
My code is:
std::thread thread = std::thread(filetodb, filesP->at(i), h);
compiler says:
Error10error C2248: 'std::thread::thread' : cannot access private member declared in class 'std::thread'c:program files (x86)microsoft visual studio 11.0vcincludexmemory06061ConsoleApplicationa
How, can I do this?
When I put boost::thread Thread; in my struct I get the error error C2248: 'boost::thread::thread' : cannot access private member declared in class 'boost::thread'
The whole struct is
struct Player {
bool key[256];
char nameString[64];
bool lMouseButton;
bool rMouseButton;
double mouseX;
double mouseY;
[Code] ....
I am currently doing the assignment about linked list. Here are some details information about what I am doing.. This program is C++ and should run on Visual Studio 2010. And it contains three file, two datastructure header and one main cpp file.
This program is trying to arrange and show some sports records. The main program which contain the functions such as reading the result text file(each result text file contain several records of athletes), removing a file, arranging the totalresult and printing it out. And the main program is already given and I cannot overwrite it.
But when I finished and try to build the solution and run it, I am not able to run the program and it give me somethings like these...
warning C4172: returning address of local variable or temporary
error C2248: 'Datastructure1::Datastructure1' : cannot access private member declared in class 'Datastructure1'
see declaration of 'Datastructure1::Datastructure1'
see declaration of 'Datastructure1'
This diagnostic occurred in the compiler generated function 'Result::Result(const Result &)'
And I have tried to comment each function part of the header file and see if can run or not. But I still fail to do so. Here are my codes...
#ifndef DATASTRUCTURE1_H
#define DATASTRUCTURE1_H
class Datastructure1 {
Public:
Datastructure1( );
[Code] ....
There are two header files and look quite long. They are all some linked list functions . I have read and learn linked list data structure before I complete this programs. However, when I complete the functions required, the function cannot be compile....
I'm unable to access private variables belonging to the object class Date, which my overloaded >> operator is a friend of. I can't see anything in my code that would be causing this error. The .h file and the definition of the problematic overloaded operator from the implementation file are below:
#ifndef DATE_H
#define DATE_H
#include <string>
using namespace std;
class Date {
public:
// Initializes a date to the default value of January 1, 1970.
[Code] .....
The error message states that the vars (month, day, year) are declared as private in the header file and then a reference is made to the lines where I attempt to access these in the .cpp file and it reads: "in this context".
Code:
std::ostrstream oss;
oss << "path for " << unit << "
" << path;
puts(oss.str());
[Code] .....
Today, I just received this new fresh error, I was constantly using them, but just come to know it is a private access violation as the last error of my program. Did I use it in the wrong way?
My code is here [URL]
void Player::Display() const
{
cout << "
Player Name: " << GetName() <<
"
Grade: " << GetGrade() << "
G.P.A. " << GetGPA() << endl;
}
The problem occurs in here, I get access violations, is there a way to this while keeping Display const or is this code valid and my problem is somewhere else and not being caught in the debugger? I tried to make the return types const - but that didn't work .....
//Getters need const twice for this to work?
const char* Player::GetName() const {return m_name;}
const int Player::GetGrade() const {return m_grade;}
const double Player::GetGPA() const {return m_gpa;}
[Code].....
So I have an ImageManager class, Board class, and Box class. In Board.h I can declare ImageManager imgr; and in Board's constructor I can use imgr and its functions and such. However, in Box.h when I try and declare ImageManager imgr; I get the error "cannot access member declared in class ImageManager". Both declarations are under private, and exactly the same, but one doesn't work. Also, is there a way to only have one instance of ImageManager?
View 19 Replies View RelatedSo I'm doing this project: [URL] ....
For now I've done a function that creates menus and prints them, and a function that creates the character as an object.
Now I want to be able to show the stats of the player on the main menu, the problem is that I don't know how to make a copy of the map as it's private...
Main
#include <iostream>
#include <string>
#include <time.h>
#include <stdlib.h>
#include <map>
#include <algorithm>
#include <stdlib.h>
#include "Create_Character.h"
#include "Menu.h"
[Code] ....
I am essentially trying to get a value from a 'Matrix' that is created. Using a function in the class where the matrix is created. But when trying to do this I get the error: Call to non-static member function without an object argument in this line when trying to call the function:
Matrix::get(sizeR, sizeC);
Giving the following program, how do i access the swapping function. I've tried swapp::change <int> ( a, b ) ; and it gave me 4 errors. Here's the code:
#include <iostream>
using namespace std;
template <typename T>
class swapp
[Code].....
In my MFC, CMyPorpertyPageDlg is derived from CPropertyPage. How to access its member function from a nonmember function in the same CPP file?.
void Non_Member_Get_PorpertyPage()
{
CMyPorpertyPageDlg* pPageDlg = ....
}
Why the void pointer passed to testb doesn't continue pointing to the allocated integer after the function call returns.
Code:
#include <stdio.h>
#include <iostream>
void* testa() {
return new int(1);
[Code] ....
How do i access the private array? I tried this and it's not working. Want i want to do is create class object in main and pass the string to constructor, and set m_make, m_model to that string. Then call the member function to output that.
const int BUFLEN = 256;
// class declaration
class CVehicle
{
[Code].....
Why do you use Private fields in a class if an outside class can change the private fields using get and set properties?
View 2 Replies View RelatedI am trying to access the private member from main . The code is as follow. I wanted to call below function from main.
uint16_t Modbus::calcCRC(uint8_t u8length)
#define MAX_BUFFER 64
typedef struct {
[Code]....
i have private data look like Peiceorder peiceOrders[20]; it looks like a array but does not have name type like int or char? why is that and what should I use the data should I write Peiceorder peiceOrders[20]=........ like that? or?
View 1 Replies View RelatedI was trying some virtual mechanism then This came to my mind
#include <iostream>
using namespace std;
class A
{
[Code].....
now My concerns is that though the function f() in B was private it gets called by the pointer of class A as it is a virtual function
so is this a violation of access control?
I need to translate a C program to C by making variables in structures private(no classes yet!) and putting public inline functions. There's a good chance that I have much more problems with my code than I'm asking right now, but I have 4 spots that I'm currently stuck in and can't access properly.
My structures:
Code: struct Container
{
private:
int count;
char** lines;
int nlines;
[Code] .....
I have a class (Quadtree) and three inner class inside (Node, Inner and Leaf). Inner and Leaf inherit from Node.
I have a function in the private scope of Quadtree.
All these are located in fun.h .
Then, in fun.cpp, I am implementing the function (which is named foo <- what a prototype name!), which takes as argument a pointer to an Inner object. Inner seems unable to be resolved however!
fun.h Code: class Quadtree {
private:
class Node{
public:
Node() { std::cout << "Node
"; }
};
class Inner : public Node {
public:
Inner() { std::cout << "Inner
[code]....
How can you actually create private fields in a C struct? I got the concept of VTable and inheriting methods aswell overriding them, but private variables can be obtained with static keyword in sourcefile. If you have variables in a struct, you can access them as soon as you got a ref to the struct. The functions are easy:
Code:
struct classA {
pointerToFunction *p;
} static void* thePrivateFoo() { }
void* publicFoo() {
thePrivateFoo(); /* or something like that */
} ...
/*in init code somewhere in the c file */ classAInstance->p = publicFoo;
But I was thinking about the variables... How is this achievable? I was thinking of a struct with only get/set functions and with no datamembers at all. All vars to be static outside the struct. But this kind of destroys the encapsulation.
