cannot call member function without object

Question

This program has the user input name age pairs and then outputs them  using a class  Here is the code    include  std lib facilities h   class Name pairs   public         bool test           void read names           void read ages           void print    private          vector lt string gt names          vector lt double gt ages          string name          double age      void Name pairs  read names          cout  lt  lt   Enter name          cin  gt  gt  name       names push back name        cout  lt  lt  endl     void Name pairs  read ages          cout  lt  lt   Enter corresponding age          cin  gt  gt  age       ages push back age        cout  lt  lt  endl     void Name pairs  print          for int i   0  i  lt  names size    amp  amp  i  lt  ages size      i               cout  lt  lt  names i   lt  lt         lt  lt  ages i   lt  lt  endl     bool Name pairs  test        int i   0     if ages i     0    names i      0   return false     else            i          return true       int main         cout  lt  lt   Enter names and ages  Use 0 to cancel  n       while Name pairs  test               Name pairs  read names         Name pairs  read ages                Name pairs  print         keep window open        However  in int main   when I m trying to call the functions I get  cannot call  whatever name is  function without object   I m guessing this is because it s looking for something like variable test or variable read names  How should I go about fixing this

User · Answer

just add static keyword at the starting of the function return type   and then you can access the member function of the class without object   for ex   static void Name pairs  read names        cout  lt  lt   Enter name        cin  gt  gt  name     names push back name      cout  lt  lt  endl

User · Answer

You are right - you declared a new use defined type  Name pairs  and you need variable of that type to use it   The code should go like this   Name pairs np  np read names

User · Answer

You need to instantiate an object in order to call its member functions  The member functions need an object to operate on  they can t just be used on their own  The main   function could  for example  look like this   int main        Name pairs np     cout  lt  lt   Enter names and ages  Use 0 to cancel  n      while np test               np read names          np read ages            np print       keep window open

User · Answer

If you want to call them like that  you should declare them static

[c++] cannot call member function without object

Examples related to c++