How to create a simple PHP cookie language toggle?

Question

I'm trying to set up, what I thought would be, a simple language switch. I thought I'd use PHP cookies, but they're not behaving as intended.

I've read a few cookie tutorials and looked at a few similar examples here on StackOverflow, but I must be missing something because it can't get it to work properly.

I'm setting the language by passing it as a URL variable (lang=en or lang=ru). That all seems to be fine. However, the code I have at the moment that sets the cookie seems to be one step behind, so initially it has no value (I'd like it to be 'en' by default), then if the user clicks the 'ENG' button it still has no value, and then if the user clicks Russian the value shows as 'en', and then if I click the 'ENG' button again the value shows as 'ru'.

Here's the code I've cobbled together:

if( $_GET['lang'] ) {
    $lang = (string)$_GET['lang'];
    setcookie( 'lang', $lang, time() + 60*60*24*30 );
} elseif( !isset($_COOKIE['lang']) ) {
    $lang = 'en';
} else {
    $lang = $_COOKIE['lang'];
}

Once I've got this working I intend to use the value of the cookie to display either the English or Russian menu using a bit of conditional PHP.

Thanks.

Answer 1

Thanks for all the suggestions - @Mob set me in the right direction, i.e. processing the cookie on another page and then sending you back to the first.

I did a bit more thinking and experimenting and I've finally solved it. I'll post the code below incase anyone else wants to use this.

On your main page put this:

<form action="language_switcher.php" method="post">
    <select name="lang">
        <option value="en"<?php if( $_COOKIE["language"] == "en" ) { echo " selected"; } ?>>English</option>
        <option value="ru"<?php if( $_COOKIE["language"] == "ru" ) { echo " selected"; } ?>>Russian</option>
    </select>
    <input type="submit" value="Select Language">
</form>

<p>Language: <?php if( isset( $_COOKIE["language"] ) ) { echo $_COOKIE["language"]; } else { echo "<em>not set</em>"; } ?></p>

Then in another file called 'language_switcher.php' put the following code:

$lang = "en";
if( isset( $_POST["lang"] ) ) {
    $lang = $_POST["lang"];
    setcookie ( 'language', $lang, time() + 60*60*24*30, '/', 'mydomain.com');
    header( "Location: /previous_page_url.php" );
}

The user chooses a language and clicks 'Select Language'. The form then sends the form value to 'language_switcher.php', which sets the cookie and then sends the user back to the previous page.

Done! :)

Answer 2

A cookie is not accessible until the setting page has been reloaded or another page has been accessed (in other words, you cannot set and access a cookie in the same page).

Check this code out :

if( $_GET['lang'] ) {
    $lang = (string)$_GET['lang'];
    setcookie( 'lang', $lang, time() + 60*60*24*30,'/' );
} elseif(  !$_GET['lang']) ) {
    $lang = 'en';
} else {
    $lang = $_GET['lang'];
}
header("Location: redirect_file.php")

Then in redirect_file.php, you redirect back to the cookie page. Perform some checks if you want to avoid redirect loops.

Answer 3

if ( !empty($_GET['language']) ) {
    $_COOKIE['language'] = $_GET['language'] === 'en' ? 'en' : 'nl';
} else if ( empty($_COOKIE['language']) ) {
    $_COOKIE['language'] = 'nl';
}
setcookie('language', $_COOKIE['language']);