尝试在main中调用函数时出错。

Question

I'm trying to call a function within my main in a program in which I am trying to convert from C to C++. All my function calls within other functions compile without error, but when it gets to the one function call in the main I get no matching function for call to contacts::menu(contacts*[5], int*, int&, char[50])'

Here is the main:

int main() {


 contacts *friends[5];
 char buffer[BUFFSIZE];
 int counter=0;
 int i=0;

 contacts::menu(friends, &counter,i,buffer);

 getch();
 return 0;
}

here is the class with the function declaration:

class contacts
{
  private:
          char *First_Name;
          char *Last_Name;
          char *home;
          char *cell;
  public:
  //constructor
         contacts()
         {
         }       

//Function declarations 
static void menu(contacts*friends ,int* counter,int i,char buffer[]);
};

Here is the beginning part of the menu function, just so you can get an idea what It was labelled:

void contacts::menu(contacts*friends,int* counter, int i,char buffer[]) 
{
  int user_entry=0;
  int user_entry1=0;
  int user_entry2=0;
  char user_entry3[50]={'\0'};
  FILE *read;
  printf("Welcome! Would you like to import a file? (1)Yes or (2) No");
  scanf("%d",&user_entry1);
  if(user_entry1==1)
    {
     printf("Please enter a file name");
     scanf("%s",user_entry3); 
     read=fopen(user_entry3,"r+");

Like I said, the other functions within my program don't receive any errors, but this one does. I'm new to C++ so I wasn't sure if there was something special I needed to add to call a function within the main.

Answer 1

Here is the problem

 contacts *friends[5];

which you pass to

void contacts::menu(contacts*friends,int* counter, int i,char buffer[]) 

You have declared an array of pointers to contacts when you pass this to the function it decays to a contacts**

To use your function with its current signature, you either need to declare your friends array as

contacts* friends = new contacts[5];

or

contacts friends[5];

In the latter case passing the array to the function will work since that will decay to contacts* which your function is expecting. The latter case is preferable as you will not have to worry about releasing the memory you create in the first case using new

Answer 2

Don't use pointers

int main()
{
    contacts friends[5];

and your code will compile.

Answer 3

菜单功能预计contacts*作为第一个参数，而你正在试图通过contacts*[]