Using end() with explode() does not work

Question

I have a string which will contain a file upload name, for example "image.jpg". I'm trying to use the explode function but it's returning an error "explode() expects parameter 2 to be string, array given in..."

I've tried looking for reasons why and comparing it to how use is instructed on PHP.Net but to no avail.

$upload_extension = end(explode(".", $feature_icon));

Solution 1

you can not use end() like you are doing since

end() -> Parameters ¶ The array. This array is passed by reference because it is modified by the function. This means you must pass it a real variable and not a function returning an array because only actual variables may be passed by reference.

so do like

$feature_icon ="image.jpg";
$upload_extension =  explode(".", $feature_icon);
$upload_extension = end($upload_extension);
var_dump($upload_extension );

Live result

Solution 2

Try doing it like this separately:

 $upload_extension = explode(".", $feature_icon);
 $upload_extension = end($upload_extension);

Solution 3

I probably should know better than to reply to a years old thread, but for what it's worth:

$upload_extension = end(explode(".", $feature_icon));

(which doesn't work because end() can only accept arrays defined in a variable, not those returned by functions) can be replaced with:

$upload_extension = explode ('.', $feature_icon) [count (explode ('.', $feature_icon)) - 1];

Whether or not you find that more or less elegant than using an intermediary variable to store the array, or using two lines of code (both as suggested above) is a matter of personal preference.

Comments

[Adrien Lacroix]

Show us how you define $feature_icon

[FThompson]

$feature_icon should be a string, not an array.

[SEngstrom]

You may want to consider pathinfo() anyway...

[DorianHuxley]

$feature_icon is just a string of the name a file has been uploaded. It's a simple $feature_icon = $_GET['feature_icon'];

[Adrien Lacroix]

@user2332946, can you show us the result of a var_dump($_GET['feature_icon']); ?

[DorianHuxley]

array(1) { [0]=> string(9) "image.jpg" }

[Dan Lugg]

@user2332946 Keep in mind, that you'll need to validate the type of $_GET['feature_icon'] to string anyway. If someone posts against your page with controls named feature_icon[], it'll auto-create an array, and you'll be passing that to explode, yielding errors.

[Dan Lugg]

Actually, +1 as end() expects an argument by reference; er go, not the result of a function call or literal value (for pedantry, a non-reference returning function call)

[vp_arth]

I hate this strict :(

[DorianHuxley]

I don't even remember asking this question - heck I don't even use PHP anymore, but thanks for the reply. It might be useful to others!