Suggested rewrite:
foreach($cre_bool_array as $name=>$value) {
  if ( !is_string($value) ) {
    continue;
  }
  $strn = "$name,";
  $strv = ($value=='t') ? 'Yes' : $value;
}

    

    while(list($name,$value) = each($cre_bool_array)) {
        if(is_string($value)) {
            $strn .= "$name,";
            $strv .= "'$value',";
            if($value == 't') {
                $strv .= "'Yes',";
            }
            continue;
        }
    }