Question

I have been working on a user database in command prompt. It lets you add a user name and password and also sign in. When I compile it I get the error no match for 'operator==' in. I am not quite exactly sure what is causing the it. Also, I have stored all of it in a class.

My header file is:

#ifndef USER_PSW_H
#define USER_PSW_H
#include <string>


class User_Psw
{
    public:
        User_Psw();
        void addToDatabase();
        void getNameIndex();
        bool PasswordMatches();
        void UserCheck();
    protected:
    private:
        int sizeOfDatabase;
        int index;
        std::string Usernames;
        std::string Password;
        std::string username;
        std::string password;
};

#endif // USER_PSW_H

The constructor is:

User_Psw::User_Psw()
{
    const int SIZE = 100;
    index = 0;
    sizeOfDatabase = 0;
    Usernames[SIZE];
    Password[SIZE];
}

The Function with the actual error is:

void User_Psw::getNameIndex()
{
    for(int i=0; i < sizeOfDatabase; i++)
    {
        if (username == Usernames[i])
        {
            index = i;
        }
    }
}

With the actual line of code containing the error being if (username == Usernames[i])

I can also add more code snippets if It is required.

Answer 1

That won’t work because you’re accessing Usernames like a vector when you actually defined the type as std::string.

You want something like this:

std::vector<std::string> Usernames;

Then you can access it like:

if (Usernames[i] == username) { // etc