Need Help: Function in class

[energetix]

Hey, I'm just started to learn that thing that calls Object-Oriented Programming. And to test myself desided to code simple "user"-object creator. So I has code like this.

#include "login.h"
#include "clearscreen.h"
#include <iostream>
#include <string.h>
using namespace std;
class user
{
public:
    char Name [128];
    char Nickname [128];
    char Passwd [15];
    int UID;
};
void hello()
{
    int i;
    cout << "\nPlease enter an number: \n (1)-register new user \n (2)-Login\n (3)-exit \n";
    cin >> i;
    choise (i);
}
int choise (int choise)
{
    if (choise==1)
    {
        registration ();
    }
    if (choise==2)
    {
        return 0; //!Here will be login
    }
    if (choise==3)
    {
        ClearScreen(); //pass 100 lines and..
        return 0; //exiting
    }
    return 0;
}
int registration ()
{
    int UID;
    user iamuser[9];  //new user each registration(int LastUID);
    //user* piamuser;      //*********************************//
    //piamuser = &iamuser; //pointers *just for test          //
    //cout << piamuser;    //*********************************//
    cout << "\nEnter number from 1 to 9; that will be your UserID: ";
    cin >> UID;
    iamuser[UID].UID=UID;
    cout << "UID1 =" << UID << "\n"; //test
    if (UID>9||UID<1)
    {
        cout << "I said 'Enter number from 1 to 9; that will be your UserID'. App will be terminated.";
        return 0;
    }
    cout << "\nEnter your real name: ";
    cin >> iamuser[UID].Name;
    cout << "\nEnter your nickname: ";
    cin >> iamuser[UID].Nickname;
    cout << "\nEnter desired password: ";
    cin >> iamuser[UID].Passwd;
    if (strlen(iamuser[UID].Passwd)>16)
    {
        cout << "\n Your password is too long. It must be < 17;\n Application exiting now...; \n Press enter";
        cin.get();
        return 0;
    }
    else
    {
        cout << "\nYour Name: " << iamuser[UID].Name << "\nYour Nickname: " 
<< iamuser[UID].Nickname 
<< "\nYour UserID: " << UID 
<< "\nYour Password: " << iamuser[UID].Passwd 
<< "\nPress Enter;";
        //  cin >> piamuser->Name;
        //  cout << iamuser.Name;
        cin.get();
        hello ();
    }
    return 0;
}

It works fine, anyway. But if I try doing something like this:

class user
{
public:
    char Name [128];
    char Nickname [128];
    char Passwd [15];
    int UID;
    displayData (int UID)
};

Combining with:

int user::displayData (int UID)
{
cout << "\nYour Name: " << iamuser[UID].Name 
<< "\nYour Nickname: " 
<< iamuser[UID].Nickname 
<< "\nYour UserID: " << UID 
<< "\nYour Password: " 
<< iamuser[UID].Passwd << "\nPress Enter;";
return 0;
}

and calling it from registration() in output the weird symbols as arrows and else appeard instead of normal name, nickname, UID and passwd.

[TinyTeeTree]

I'm not sure how exactly you combined the two, but you cant access iamuser[UID].Name from inside a member function!

member functions have access to the private and public members of that object.

so the proper way to combine would be

class user
{
public:
    char Name [128];
    char Nickname [128];
    char Passwd [15];
    int UID;
    void displayData (int UID);
};

Combining with:
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void user::displayData (int UID)
{
   cout << "\nYour Name: " << Name 
   << "\nYour Nickname: " 
   << Nickname 
   << "\nYour UserID: " << UID 
   << "\nYour Password: " 
   << Passwd << "\nPress Enter";
return 0;
}

first off: that functions returns nothing, hence void.
second off: the variables visible inside the function are only ones declared inside that function, which you got none, or members of the object.

[TinyTeeTree]

and you dont need an array of users, one is enough in your example

[dem7w2]

First off, you should take a look at the cplusplus tutorials on
1) arrays,
2) functions, and
3) classes

Secondly...

    int UID;
    user iamuser[9];      //The array is only of size 9.
                          //This means you can only access iamuser[0] to iamuser[8]

    cout << "\nEnter number from 1 to 9; that will be your UserID: "; //should say 0 to 8
    cin >> UID;

    iamuser[UID].UID=UID;

I recommend using do while loops to check if the user's input is valid.

do
{
    cin >> UID;
}while(UID is not valid...);

As for displaying stuff: you misunderstand how to use variables in classes. Since displayData is user's function, it can access all of the variables and function in user.

//call your function like so
iamuser[USD].displayData();
//have your function like this...
int user::displayData()
{
cout << "\nYour Name: " << Name << endl;
//notice how I didn't say iamuser[UID].Name.
//it's just Name because there is only ONE Name for the ONE instance of this class.
}

[energetix]

dem7w2, thanks that worked anyway, will read mor man's and tutorials from series "C++ for Dummies"

[dem7w2]

this helps too: http://www.cplusplus.com/doc/tutorial/