Question

I cannot get the loop to work in my simple js login script. When i try to login with any login other than the last one in the array (user3 and pass3) it returns false.

What am I doing wrong?

I have tried both == and ===.

var userLogins = [{user:"user1", password:"pass1"},{user:"user2", password:"pass2"},{user:"user3", password:"pass3"}]
var success = null;
function logon(user, pass) {
    userok = false;
    for (i = 0; i < userLogins.length; i++)
    { 
        if(pass == userLogins[i].password && user == userLogins[i].user )
        {
            success = true;
        }
        else
        {
            success = false;
        }
    }
    secret(success);
}

function getData() {
    var user = document.getElementById("userid").value;
    var password = document.getElementById("password").value;
    logon(user, password);
}

function secret(auth){
    if(auth)
    {
        show('success');
        hide('login');
    }
    else
    {
        show('error');
        hide('login');
    }
}

function show(show) {
    document.getElementById(show).className = "show";
}
function hide(hide) {
    document.getElementById(hide).className = "hide";
}

Answer 1

for (i = 0; i < userLogins.length; i++)
{ 
    if(pass == userLogins[i].password && user == userLogins[i].user )
    {
        success = true;
    }
    else
    {
        success = false;
    }
}

You need a break in there, otherwise your true value for success simply gets overwritten with false on the next iteration… except for the last possible credentials, for which there is no “next” iteration.

Once you’ve done that, you don’t actually need the else branch at all:

var success = false;
for (i = 0; i < userLogins.length; i++) { 
    if (pass == userLogins[i].password && user == userLogins[i].user) {
        success = true;
        break;
    }
}