function valAlphaNum($str)
{
    if (valNonEmpty($str)) {
        return ctype_alnum($str);
    } else {
        return false;
    }
}
 function processPassword($name)
 {
     if ($this->isPosted()) {
         if (isset($_POST[$name])) {
             $this->setElementValue($name, $this->stripSlashesInVals(trim($_POST[$name])));
         }
         if ($this->elements[$name]["validate"] === true) {
             if (!valNonEmpty($this->elements[$name]["value"])) {
                 $this->errMsg[] = $this->elements[$name]["error"];
             }
         } elseif ($this->elements[$name]["validate"] !== false) {
             if (!$this->valComparison($name, $this->elements[$name]["validate"])) {
                 $this->errMsg[] = $this->elements[$name]["error"];
             }
         }
     }
     $str = "<input name=\"{$name}\" type=\"password\" class=\"" . $this->elements[$name]["style"] . "\" size=\"" . $this->elements[$name]["size"] . "\" maxlength=\"" . $this->elements[$name]["maxlength"] . "\"";
     $str .= $this->elements[$name]["default"] ? " value=\"" . htmlentities($this->elements[$name]["value"], ENT_QUOTES) . "\">" : " value=\"\">\n";
     return $str;
 }