Building a PHP 5 Form Processor: Using the Form Processor Package - The complete application at a glance: listing the complete code of the form processor (
Page 5 of 5 )
To summarize, here’s the complete source code for the form processing package:
// class formElement
// creates form elements
class formElement{
private $html='';
public function __construct($type='text',$attributes=array
('name'=>'default'),$options=array()){
// check for <input> elements
if(preg_match("/^
(text|radio|checkbox|password|hidden|submit|reset|button|image|
file)$/",$type)){
$openTag='<input type="'.$type.'" ';
$closeChar=' ';
$closeTag='/>';
}
// check for <textarea> and <select> elements
else if(preg_match("/^(textarea|select)$/",$type)){
$openTag='<'.$type.' ';
$closeChar='>';
$closeTag='</'.$type.'>';
}
else{
throw new Exception('Invalid element type');
}
if(!is_array($attributes)||count($attributes)<1){
throw new Exception('Invalid number of attributes for
<'.type.'> element');
}
// loop over element attributes
$elemAttributes='';
foreach($attributes as $attribute=>$value){
if(empty($attribute)||empty($value)){
throw new Exception('Invalid attribute or value
for <'.type.'> element');
}
// check for 'required' attribute - add client-side
validation
$attribute=='required'?JSGenerator::addValidation
($attributes
['name'],$value):$elemAttributes.=$attribute.'="'.$value.'" ';
}
// check for <select> options
$selOptions='';
if(count($options)>0){
foreach($options as $value=>$text){
if(empty($value)||empty($text)){
throw new Exception('Invalid value or text
for <'.type.'> element');
}
$selOptions.='<option value="'.$value.'">'.$text.'</option>';
}
}
// build form element(X)HTML output
$this->html.=$openTag.trim
($elemAttributes).$closeChar.$selOptions.$closeTag;
}
// return complete (X)HTML
public function getHTML(){
return $this->html;
}
}
// class JSGenerator
// generates client-side validation functions
abstract class JSGenerator{
private static $js=array();
// load external JavaScript validating functions
public function initializeFunctions(){
self::$js['ext']='<script language="javascript"
src="functions.js"></script>';
}
// add JavaScript validating function to selected field
public function addValidation($fieldName,$valData){
if(!is_array($valData)){
throw new Exception('Invalid client-side validation
array');
}
$obj='document.getElementsByTagName("form")[0].elements
["'.$fieldName.'"]';
// obtain client-side validating function & error message
list($valFunction,$errorMessage)=$valData;
self::$js['int'].='if
(!'.$valFunction.'('.$obj.',"'.$errorMessage.'")){'.$obj.'.focus
();return false};';
}
// return JavaScript code
public function getCode(){
return self::$js['ext'].'<script
language="javascript">function validate(){'.self::$js['int'].'}</script>';
}
}
// class formValidator
// performs server-side form validation
class formValidator{
private $errors=array();
public function __construct(){}
// validate empty field
public function validateEmpty($field,$errorMessage,$min=4,$max=32){
if(!isset($_POST[$field])||trim($_POST[$field])
==''||strlen($_POST[$field])<$min||strlen($_POST[$field])>$max){
$this->errors[]=$errorMessage;
}
}
// validate integer field
public function validateInt($field,$errorMessage){
if(!isset($_POST[$field])||!is_numeric($_POST[$field])
||intval($_POST[$field])!=$_POST[$field]){
$this->errors[]=$errorMessage;
}
}
// validate numeric field
public function validateNumber($field,$errorMessage){
if(!isset($_POST[$field])||!is_numeric($_POST[$field])){
$this->errors[]=$errorMessage;
}
}
// validate if field is within a range
public function validateRange($field,$errorMessage,$min=1,$max=99){
if(!isset($_POST[$field])||$_POST[$field]<$min||$_POST
[$field]>$max){
$this->errors[]=$errorMessage;
}
}
// validate alphabetic field
public function validateAlphabetic($field,$errorMessage){
if(!isset($_POST[$field])||!preg_match("/^[a-zA-Z]
+$/",$_POST[$field])){
$this->errors[]=$errorMessage;
}
}
// validate alphanumeric field
public function validateAlphanum($field,$errorMessage){
if(!isset($_POST[$field])||!preg_match("/^[a-zA-Z0-9]
+$/",$_POST[$field])){
$this->errors[]=$errorMessage;
}
}
// validate email
public function validateEmail($field,$errorMessage){
if(!isset($_POST[$field])||!preg_match
("/.+@.+\..+./",$_POST[$field])||!checkdnsrr(array_pop(explode
("@",$_POST[$field])),"MX")){
$this->errors[]=$errorMessage;
}
}
// private method 'windnsrr()' for Windows systems
private function windnsrr($hostName,$recType=''){
if(!empty($hostName)){
if($recType=='')$recType="MX";
exec("nslookup -type=$recType $hostName",$result);
foreach($result as $line){
if(preg_match("/^$hostName/",$line)){
return true;
}
}
return false;
}
return false;
}
// check for errors
public function checkErrors(){
if(count($this->errors)>0){
return true;
}
return false;
}
// return errors
public function displayErrors(){
$errorOutput='<ul>';
foreach($this->errors as $err){
$errorOutput.='<li>'.$err.'</li>';
}
$errorOutput.='</ul>';
return $errorOutput;
}
}
// class formGenerator
// builds up the web form
class formGenerator{
private $html=array();
private $action;
private $method;
public function __construct($action='',$method='post'){
// setup form attributes
$this->action=empty($action)?$_SERVER
['PHP_SELF']:$action;
$this->method=$method!='post'||$method!
='get'?'post':$method;
}
// add form element
public function addElement($type='text',$attributes=array
('name'=>'default'),$options=array()){
if(!$elem=new formElement($type,$attributes,$options)){
throw new Exception('Failed to instantiate '.$type.'
object');
}
$this->html[]=$elem->getHTML();
}
// add form part
public function addFormPart($formPart='<br />'){
$this->html[]=trim($formPart)==''?'<br />':$formPart;
}
// display form
public function display(){
$formOutput='<form action="'.$this->action.'"
method="'.$this->method.'">';
foreach($this->html as $html){
$formOutput.=$html;
}
$formOutput.='</form>';
// load global JavaScript checking functions
JSGenerator::initializeFunctions();
// append JavaScript code to general (X)HTML output
$formOutput.=JSGenerator::getCode();
return $formOutput;
}
}
Wrapping up
In this article, I went through the makings of an extensible form processing library, for use either in PHP 5, or –- with minor modifications -- in PHP 4. If you’re serious about taking PHP to more complex levels of development, I encourage you to grab the proper theory behind processing forms through the object-oriented paradigm, and then make your own way, either by extending the package I developed or by picking up an existing one. As always, the choice is up to you. Meet you in the next PHP tutorial!
