how to use the operators AND, OR in the IF statement in PHP

Question

I tried to use the operators AND, OR in an IF statement in a PHP script like this:

if($user[id]=='1' AND (($_GET['f']=='f-ppas') || ($_GET['f']=='f-kua'))){
   .....
}

But the result is wrong. Can anyone help me?

Define "wrong". PS: it's weird you're using `AND` together with `||` (instead of `OR`) in the same expression - looks inconsistent — zerkms, Apr 03 '14 at 00:47
`$user[id]` will cause a PHP notice if it doesn't have `'` around the key. Should be `$user['id']` — Adam Merrifield, Apr 03 '14 at 00:50
I don't know what you expected, but as you use `A AND (B OR C)` this evaluates to `(A AND B) OR (A AND C)`. Maybe not what you expected. — Phidelux, Apr 03 '14 at 00:51
@zerkms I dont think so. I do not think it is not a problem using a statement like that. — responsiblevebri, Apr 03 '14 at 00:53
@responsiblevebri: I didn't say it's a *problem*. I said it looks *inconsistent*. — zerkms, Apr 03 '14 at 00:53
What about: `if(($user['id'] == 1) && (($_GET['f'] == 'f-ppas') || ($_GET['f'] == 'f-kua'))) {}` — Darren, Apr 03 '14 at 00:57
It Seems you have too many brackets try this --- if ($user[id] == '1' && $_GET['f'] == 'f-ppas' || $_GET['f'] == 'f-kua' ){ ..... } — Tasos, Apr 03 '14 at 01:06

score 0 · Accepted Answer · edited May 23 '17 at 11:43

0

Change AND to &&

if($user['id']=='1' && (($_GET['f']=='f-ppas') || ($_GET['f']=='f-kua'))){
   .....
}

The AND operator has some precedence problems.

$this = true;
$that = false;

$truthiness = $this and $that;

$truthiness above has the value true. Why? = has a higher precedence than and. The addition of parentheses to show the implicit order makes this clearer:

 ($truthiness = $this) and $that

If you used && instead of and in the first code example, it would work as expected and be false.

Reference: 'AND' vs '&&' as operator

edited May 23 '17 at 11:43

Community

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answered Apr 03 '14 at 00:56

Nikko Madrelijos

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Then you have problems with the logic of the IF statement. I don't understand what you are trying to achieve. update your question so we could answer it correctly :) – Nikko Madrelijos Apr 03 '14 at 01:03
Yes it will work but in some cases like what i stated in my examples, the `AND` Operator has precedence problems. – Nikko Madrelijos Apr 03 '14 at 01:09
It's quite unfair to tell that operator has some precedence problems. It's not. The precedence is well defined. So it's a programmer who uses an operator without checking its precedence who has some problems. – zerkms Apr 03 '14 at 01:14
Okay, wrong choice of word. The `AND` operator if used carelessly, it will generate the wrong output. :p – Nikko Madrelijos Apr 03 '14 at 01:16

how to use the operators AND, OR in the IF statement in PHP

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