PHP if statement: all conditions approved - php

Question

I've checked a condition in my script, but am having problems with the if statement. Please check my code:
function __construct($user=null)
{
parent::__construct();
require_once 'model/chanell_model.php';
$this->theme->msg='.....';
$this->db = new chanell_model();
if ($user==null && !parent::isLog()){
$this->themes=2;
}elseif ($user===null){
echo 'print';
$this->db->getChanellData();
}elseif($user!==null){
echo 'print';
}else{
$this->db->getChanellData($user);
}
}
How could be possible in same time $user == null and also $user != null.
In this code both echo commands will work .
I've also used == instead of === .
Sorry for my English. Any help would be great.

Answer 1

Take a long breath
if ($user===null){ echo 'bye'; }else{ echo 'hi'; }
if this piece of code will write 'bye' and 'hi' at the same time, so it's time to change your computer... :)
More seriously,
Try to debug your code and XDEBUG will be your friend for life :)
And for the immediate test, you can run your constructor as follow
function __construct($user = NULL) {
parent::__construct();
require_once 'model/chanell_model.php';
$this->theme->msg = '.....';
$this->db = new chanell_model();
$debug = TRUE;
$executionId = uniqid();
$debugMessage = '';
if ((is_null($user)) && (!parent::isLog())){
$this->themes=2;
if ($debug) {
$debugMessage .= "First condition executed, id: <" . $executionId . ">\n";
}
}
elseif ($user===null){
echo 'print';
$this->db->getChanellData();
if ($debug) {
$debugMessage .= "Second condition executed, id: <" . $executionId . ">\n";
}
}
elseif($user!==null){
echo 'print';
if ($debug) {
$debugMessage .= "Third condition executed, id: <" . $executionId . ">\n";
}
}
else{
$this->db->getChanellData($user);
if ($debug) {
$debugMessage .= "Fourth condition executed, id: <" . $executionId . ">\n";
}
}
if ($debug) {
print $debugMessage;
}
}
You will see, that the same execution id (simulated by uniid) can not run twice
Also :
use `NULL` instead of `null`
to test if value is null use `is_null()`
Fourth condition will never run!!
Do not forget to remove the debug mess once you've finished