PHP to remove duplicate words from strings and generate index strings

The

/php the repeating word in the string, generates an index string, and the string parameter is an already-word-handled string
 //--------------------------------------------------
  function Getindextext ($okstr, $ilen =-1)
  {
    if ($okstr = = "") return ";
    $ws = Explode ("", $okstr);
    $okstr = "";
    $wks = "";
    foreach ($ws as $w)
    {
      $w = Trim ($w);
     //Excluding characters less than 2
      if (strlen ($w) <2) re-enters;
     //Excluding numbers or dates
      if (!ereg ("[^0-9:-]", $w)) re-enters;
      if (strlen ($w) ==2&&ord ($w [0]) >0x80) re-enters;
      if (isset ($wks [$w]) $wks [$w]++;
      Else $wks [$w] = 1;
   }
    if (Is_array ($wks))
    {
      Arsort ($wks);
      if ($ilen ==-1)
      {foreach ($wks as $w => $v) $ Okstr. = $w. " "; }
      Else
      {
         foreach ($wks as $w => $v) {
          if (strlen ($ OKSTR) +strlen ($w) +1) < $ilen) $okstr. = $w. " ";
          Else break;
       }
     }
   }
    return Trim ($OKSTR);
 }?>