Getting A 0 or 1 Value from MYSQL With PHP

Question

I'm trying this code to check if a user is verified and redirecting them if they are not. I'm having trouble with the result as it keeps redirecting me regardless of if I am verified or not. Here is the code:

<?php
    if(loggedin()){ 
    $check_active_sql = mysql_query("SELECT * FROM members WHERE username = '$username'") or die(mysql_error());
    while ($check_active_res = mysql_fetch_array($check_active_sql)) {
        $active = $check_active_res['active'];
            if($active == "0"){
                header("Location: login.php?verify=true");
            }
            else
            {
            }
        }
    };
?>

Thank you

It's difficult to know where the problem is. Please follow the regular debugging process by [`var_dump`ing](http://www.php.net/manual/en/function.var-dump.php) your variables at different points and provide us with the results. You'll either solve the problem yourself, or you'll give us more information to help you. — Adi, Mar 16 '13 at 09:27

score 1 · Answer 1 · answered Mar 16 '13 at 10:23

1

I'm assuming that once a user logs in you set a field in the database to 1 Why not use sessions instead of using this way?

Simply as soon as you login a user put the following code

session_start();
$_SESSION['logged_in'] = 1;

Now, to check if a user is logged in, simply add this function

function check_login() {
if($_SESSION['logged_in'] == 1){
return true;
} else {
return false;
}

then if you want to redirect him simply do the following

if(!check_login()) {
header('location: http://website.com');
}

answered Mar 16 '13 at 10:23

Ali

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Sorry, in this case $active relates to weather the member has validated their account via email so a session wouldn't work in this case - However I will definitely use this code example if I decide to log members who are online, thanks. Do you know of any ways of ensuring that a member definately validates their account? – user2152265 Mar 16 '13 at 14:50

sandip · Accepted Answer · 2013-03-16T10:34:21.270

-1

try by using empty() as:

     if(empty($active) && $active!=1){
         header("Location: login.php?verify=true");
     }else{

     }

instead of

     if($active == "0"){}

empty — Determine whether a variable is empty

In other words, it will return true if the variable is an empty string, false, array(), NULL, “0?, 0, and an unset variable.

edited Mar 16 '13 at 10:34

answered Mar 16 '13 at 09:21

sandip

3,279
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Would please explain why? – Adi Mar 16 '13 at 09:23
No that doesn't work either – user2152265 Mar 16 '13 at 09:25
While your explanation is valid to document the behaviour of [`empty()`](http://php.net/manual/en/function.empty.php), you give no clue to the OP as why would this solve his problem – Adi Mar 16 '13 at 09:29
It's ok, I understand how that would work but my database actually has the number 0 in the database by default and changes to 1 when verified - I guess I'd have to get rid of the 0 value – user2152265 Mar 16 '13 at 09:35
@user2152265 gr8! you understood this, as you said you have values 0 & 1 (if confirmed) the above function will do the job as it checks for (string, false, array(), NULL, “0?, 0, and an unset variable) , you can also modify more precisely as if(empty($active) && $active!=1){} – sandip Mar 16 '13 at 09:41
1

`empty` is the same as `== false`. Don't use `empty` *unless you don't know whether the variable you're testing exists or not*. – deceze Mar 16 '13 at 09:41
Tried the answer that you gave but for some reason now it logs me in if I'm not verified (0) and redirects me if I am (1) – user2152265 Mar 16 '13 at 09:45
Ok, I just noticed the ! so I removed that and it works however I now get an error on the header ( Cannot modify header information )? – user2152265 Mar 16 '13 at 09:48
@user2152265 I think that is a different problem , for more about this refer this http://stackoverflow.com/questions/8028957/headers-already-sent-by-php – sandip Mar 16 '13 at 09:54
@user2152265 Your welcome! , I am happy that my answer helped you – sandip Mar 16 '13 at 10:18

Getting A 0 or 1 Value from MYSQL With PHP

2 Answers2