if (!is_array($data)) {
$data = array($data);
}
//foreach over $data

With typecasting I can do this:

$data = (array) $data;
//foreach over $data

I also use it regularly to ensure that the correct type is returned by a method.

Please correct me if you think this is wrong.

The reason why is you have to force the variable to become an integer for security.

Consider a page which uses a GET request:

product.php?id=123

If I’m a nasty hacker, I can potentially do this:

product.php?id=’ or ‘1′ = ‘1

Which could turn (behind the scenes) into

“SELECT * FROM admin_users WHERE username = ‘admin’ and password = ‘xxx’ OR ‘1′ = ‘1′;”

PHP won’t automatically convert my GET variable into an integer. However, if I force it to, by casting, the string: ‘ or ‘1′ = ‘1 will never be passed to my database, but the string 123 will be passed because it can be cast.

Hope that explains it.

echo ((int)’1024′) / 100;
echo ‘1024′ / 100;
echo ‘1024′ / ‘100′;

So why?

It is not only an overkill but also contributing to the global warming. I mean performing senseless computations. Besides calling a function takes time, while (int) is really fast.

to computerzworld:
if implode and (string) don’t do what you want then use foreach

serialize(array) will turn your array into a string.
unserialize(string) will turn it back into an array.

Or >>

$string = “”;
foreach ($array as $key => $value):
$string .= $value . ‘ ‘;
endforeach;

$id = number_format($_POST['id'], 0, “”, “”);
$sql = “SELECT * FROM table WHERE id = $id”;

This way, if the posted value is not a integer, 0 is returned at the query doesn’t fail?

sprintf(‘SELECT * FROM table WHERE id = %d’, mysql_real_escape_string($_POST['input']));