PHP - 显示问题包括另一个.php文件

Question

I just write simple code to display translated text based on user borowser language. It looks i did something wrong becuase when i use sk.php it display corret SK translate but when it use cs.php it having problem with translate and isntead of any text it just display "s" everywhere.

I was thiking problem can be in translate file so I makde duplicity of sk.php and rename it to cs.php and it didn't help.

Guys is here somebody who can give me an advise where can be a problem?

 public function fetchByVinAxnmrss($con) {
     $success = false;
     if($this->vin){
        $lang = $_SERVER['HTTP_ACCEPT_LANGUAGE'];
        $_SESSION['lang'] = $lang;
        if(isSet($lang))
        {
            setcookie('lang', $lang, time() + (3600 * 24 * 30));
        }
        else if(isSet($_COOKIE['lang']))
        {
            $lang = $_COOKIE['lang'];
        }
        else
        {
            $lang = 'cs';
        } 
        switch ($lang) 
        {
            case 'sk':
            $lang_file = 'sk.php';
            break;
            case 'cs':
            $lang_file = 'cs.php';
            break;
            default:
            $lang_file = 'cs.php';
        }
        include_once 'languages/'.$lang_file;
     try{
        //$sql = "SELECT * FROM `axnmrs_cases` WHERE `vin` = ':vin' ORDER BY STR_TO_DATE(date_created, '%Y-%m-%d %H:%i:%s') LIMIT 30";
        $sql = "SELECT * FROM axnmrs_cases WHERE vin = :vin ORDER BY date_created DESC LIMIT 60";
        $stmt = $con->prepare( $sql );
        $stmt->bindValue( "vin", $this->vin, PDO::PARAM_STR );
        $stmt->execute();
            while ($row = $stmt->fetch()){
            echo $lang_file;    
            echo  "<dd>".$lang['YES']."</dd>"

p.s. I am debuging with that echo $ lang_file to see which file are opening.

EDIT: adding part of my cs.php file:

$lang = array();

//All
$lang['YES'] = 'Ano';
$lang['NO'] = 'Ne';
$lang['NOT_AVALIABLE'] = 'Není k dispozici';
$lang['CURRENCY'] = 'Měna';

Answer 1

$lang is not an array. You've made it a string, and PHP does let you treat a string as an array. e.g.

$foo = 'This is a test';
        01234567890123

echo $foo[6]; // outputs s

Since you're getting c everywhere, it's probably because:

$lang = 'cs';
         01

echo $lang['YES'];
becomes 
echo $lang[0];
becomes
echo 'c';