PHP scoping and global

Question

I have the following code:

<html>
<body>
    <h1><?isFoo();?></h1>
</body>
</html>
<?php
$foo_app_cookie_val = "foo";

function isFoo() {
    global $foo_app_cookie_val;
    echo "in isFoo: '$foo_app_cookie_val'<br/>";
    return isApp($foo_app_cookie_val);
}
?>

The output I'm getting is:

isFoo: ''

Why aren't I seeing the actual value of $foo_app_cookie_val?

`$foo_app_cookie_val` is undefined by the time `isFoo()` is called. — Antony, Jan 16 '14 at 15:38
right. yo uneed to define these things before calling hem. you are running above. also change that to — Kai Qing, Jan 16 '14 at 15:39
@GertB. I don't see anything about deprecation here: http://www.php.net/manual/en/language.basic-syntax.phptags.php. — vbo, Jan 16 '14 at 15:42
@vbo ok, maybe a bad choice of words, but it would be better to change it — Gert B., Jan 16 '14 at 15:44
@GertB. Found this question: http://stackoverflow.com/questions/200640/are-php-short-tags-acceptable-to-use — vbo, Jan 16 '14 at 15:45

score 10 · Accepted Answer · answered Jan 16 '14 at 15:39

10

$foo_app_cookie_val is being set to foo after <h1><?isFoo();?></h1> is output. Change the script to:

<?php
$foo_app_cookie_val = "foo";

function isFoo() {
    global $foo_app_cookie_val;
    echo "in isFoo: '$foo_app_cookie_val'<br/>";
    return isApp($foo_app_cookie_val);
}
?>
<html>
<body>
    <h1><?isFoo();?></h1>
</body>
</html>

answered Jan 16 '14 at 15:39

Michael

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`**facepalm**` I'm too used to languages that don't take declaration order into consideration :( – ThaDon Jan 16 '14 at 17:19

score 4 · Answer 2 · answered Jan 16 '14 at 15:39

isFoo() is being called before you've set the value of $foo_app_cookie_val. Try moving the large block of PHP code to the top of the file, like this:

<?php
$foo_app_cookie_val = "foo";

function isFoo() {
    global $foo_app_cookie_val;
    echo "in isFoo: '$foo_app_cookie_val'<br/>";
    return isApp($foo_app_cookie_val);
}
?>
<html>
<body>
    <h1><?isFoo();?></h1>
</body>
</html>

Where the function is actually declared doesn't matter. What matters is where you call the function in relation to setting the global variable.

PHP scoping and global

2 Answers2