title: str_replace with Arabic character
body: <p>i try to replace some arabic caractere with another symbole
  some arbic caractere is replaced but one of this caractere it not replaced 
  first i try to split the word 
  second try to replace the caractere
  the caractere is َ ً ٍ ِ ْ ُ all this are replaced but the problem is with this caractere ّ
  <strong>strong text</strong>
  this is the code</p>
  
  <pre><code>   $spelling="";
  
  function str_split_unicode($str, $l = 0) {
  
  if ($l &gt; 0) {
  
  $ret = array();
  
  $len = mb_strlen($str, "UTF-8");
  
  for ($i = 0; $i &lt; $len; $i += $l) {
  
  $ret[] = mb_substr($str, $i, $l, "UTF-8");
  
  }
  return $ret;
  }
  return preg_split("//u", $str, -1, PREG_SPLIT_NO_EMPTY);
  }
  
  if(isset($_POST['txt_word'])){
  
   $spelling = implode("  ", str_split_unicode($_POST['txt_word']));
  
  }
  
  
   $search  = array('ّّ ','ً ','ٍ ','ٌ ','ُ ','َ ','ِ ','ْ ');
  
  $replace = array('0/','/0','/0','/0','/','/','/','0');
  
  $subject= str_replace($search, $replace,  $spelling);
  
  $alphabet=array('أ','ا','ب','ت','ث','ج','ح','خ','د','ذ','ر','ز','س','ش','س','ص','ط','ظ','ع','غ','ف','ق','ل','م','ن','ه','و','ي','لا','ة','إ','ئ','ؤ','ك','ى','ء');
  
  $rep=array('','','','','','','','','','','','','','','','','','','','','','','','','','','','','','','','','','');
  
  $res=str_replace($alphabet,$rep,$subject);
  </code></pre>