Thread: Need some help with a C++ program. Logging in and toupper.

Originally Posted by sipth

If I have alot of users the program seems to only read the first line of user name and password. How do I make the program scan the entire "Personal.txt" to allow it to login?

You have a few options. One option is to keep reading from the file until you find an entry that matches. If there is no such entry, then the credentials are incorrect. A possibly better option is to define a struct/class to model a user, then create a vector of objects of that struct/class. You read all the entries from the file into the vector of objects. Then, you search the vector for the entry with the given username/password.

Originally Posted by laserlight

You have a few options. One option is to keep reading from the file until you find an entry that matches. If there is no such entry, then the credentials are incorrect. A possibly better option is to define a struct/class to model a user, then create a vector of objects of that struct/class. You read all the entries from the file into the vector of objects. Then, you search the vector for the entry with the given username/password.

Can you give me of an example of the first method of reading the file until i find an entry that matches?

I currety changed mine to this but I'm not sure how to continue from it.

Code:

{


		cout << "Please login. Enter name<space>password: ";
		cin >> user1 >> password1;


		while (!inputfile.eof())
		if (user1 == user && password1 == password)
		{
			cout << "WELCOME";
		}
		else
		{
			cout<<"Failed";
		}


	}

A simple example:

Code:

bool authenticated = false
while (infile >> name >> user >> password)
{
    if (user == user1 && password == password1)
    {
        authenticated = true;
        break;
    }
}

Originally Posted by laserlight

A simple example:

Code:

bool authenticated = false
while (infile >> name >> user >> password)
{
    if (user == user1 && password == password1)
    {
        authenticated = true;
        break;
    }
}

I'm not sure where I'm going wrong. Just now, it only reads the first line now it only reads the last line.

Code:

{


        cout << "Please login. Enter name<space>password: ";
        cin >> user1 >> password1;






        while (infile >> name >> user >> password)
        if (user1 == user && password1 == password)
        {
            cout << "WELCOME";
            break;
        }
        else
        {
            cout<<"Failed";
            break;
        }


}

I think you mean to say that it only reads the first line.

Look at your loop. Suppose (user1 == user && password1 == password) evaluates to true. You then print a message then break from the loop. Otherwise, you print a different message then break from the loop. Therefore, we can rewrite your loop to be:

Code:

if (infile >> name >> user >> password)
    if (user1 == user && password1 == password)
    {
        cout << "WELCOME";
    }
    else
    {
        cout<<"Failed";
    }

That is, it isn't a loop.

Originally Posted by laserlight

I think you mean to say that it only reads the first line.

Look at your loop. Suppose (user1 == user && password1 == password) evaluates to true. You then print a message then break from the loop. Otherwise, you print a different message then break from the loop. Therefore, we can rewrite your loop to be:

Code:

if (infile >> name >> user >> password)
    if (user1 == user && password1 == password)

Isit possible if I sent you a private message with the code? I cant seem to solve the logging in part and I'm really frustrated
    {
        cout << "WELCOME";
    }
    else
    {
        cout<<"Failed";
    }

That is, it isn't a loop.

Isit possible If I sent you a private message inclusive of my code? It would help greatly if you could help me see what the problem is. I cant seem to solve the logging in part.

EDIT: Seems like I cant send a private message, it's okay i guess...

It's better if you post it publically so everyone can see. That way, anyone can help.