Simple PHP Function Boolean Problem - php

Someone please explain to me why this doesn't work, and what I am doing wrong. For some reason, when I run the function validateUsername, the $error variable remains completely unchanged, instead of evaluating to true. How is this possible?
Yet, if I remove the code within the function and run it straight without a function call, it works. The example below is so simple it is practically pseudo code, and yet it doesn't work. Is this behavior unique to PHP? I don't want to run into this again in some other language.
<?php
$username = 'danielcarvalho';
$error = false;
function validateUsername()
{
if (strlen($username) > 10)
{
$error = true;
}
}
validateUsername();
if ($error == false)
{
echo 'Success.';
}
else
{
echo 'Failure.';
}
?>

This isn't working because $username isn't available within the scope of your validateUsername function. (Neither is the $error variable.) See the variable scope section of the PHP manual for more information.
You could fix this by adding global $username, $error; within your function, although this isn't a particularly elegant approach, as global variables are shunned for reasons too detailed to go into here. As such, it would be better to accept $username as an argument to your function as follows:
<?php
function validateUsername($username) {
if (strlen($username) > 10) {
return false;
}
return true;
}
if (validateUsername('danielcarvalho')) {
echo 'Success.';
}
else {
echo 'Failure.';
}
?>

$error has local scope in function validateUsername. To access global variables, use global keyword.
Read about scopes here. Change your function to:
function validateUsername($username)
{
global $error;
if (strlen($username) > 10)
{
$error = true;
}
}
validateUsername($username);
Better implementation using function parameter:
function validateUsername($username, &$error)
{
if (strlen($username) > 10)
{
$error = true;
}
}
validateUsername($username, $error);
Another implementation:
function validateUsername($username)
{
if (strlen($username) > 10)
{
return true;
}
return false;
}
$error = validateUsername($username);

Related

Why does the validation email returns an error?

I am developing a Register/Login system with validation. Registering system is working well. For example, when I register the same email twice, the following message appears:
Email already registered!
However, when I log-in with the same e-mail and password, an error occurs. The following message appears as a validation error:
Email not registered!
Even if the email is registered in DB.
Code for e-mail validation:
<?php
public function validateEmail($par)
{
if (filter_var($par, FILTER_VALIDATE_EMAIL)) {
return true;
} else {
$this->setErro("Invalid Email!");
return false;
}
}
public function validateIssetEmail($email, $action = null)
{
$b = $this->cadastro->getIssetEmail($email);
if ($action == null) {
if ($b > 0) {
$this->setErro("Email already registered!");
return false;
} else {
return true;
}
} else {
if ($b > 0) {
return true;
} else {
$this->setErro("Email not registered!");
return false;
}
}
}
Code for login controller:
<?php
$validate = new Classes\ClassValidate();
$validate->validateFields($_POST);
$validate->validateEmail($email);
$validate->validateIssetEmail($email,"login");
$validate->validateStrongSenha($senha);
$validate->validateSenha($email,$senha);
var_dump($validate->getErro());
Code for class login:
<?php
namespace Models;
class ClassLogin extends ClassCrud
{
# Returns user data
public function getDataUser($email)
{
$b = $this->selectDB(
"*",
"users",
"where email=?",
array(
$email
)
);
$f = $b->fetch(\PDO::FETCH_ASSOC);
$r = $b->rowCount();
return $arrData = [
"data" => $f,
"rows" => $r
];
}
}
My getIssetEmail method exists on Register code only.
# Check directly at the bank if the email is registered
public function getIssetEmail($email)
{
$b = $this->selectDB(
"*",
"users",
"where email=?",
[
$email
]
);
return $r = $b->rowCount(); // returns the amount of rows in the search
}
And ClassPassword
<?php
namespace Classes;
use Models\ClassLogin;
class ClassPassword
{
private $db;
public function __construct()
{
$this->db = new ClassLogin();
}
# Create password's hash to save in DB
public function passwordHash($senha)
{
return password_hash($senha, PASSWORD_DEFAULT);
}
# Verify if password's hash is correct
public function verifyHash($email, $senha)
{
$hashDb = $this->db->getDataUser($email);
return password_verify($senha, $hashDb["data"]["senha"]);
}
}
This is not an answer but hopefully it will help in debugging.
First, I'm going to change your code. This is 100% a style choice but I personally think it is easier to follow. If you have an if statement that always returns, you don't technically need an else. Once again, this is a style choice and you don't have to follow it.
Second, if you can, try adding logging into your workflow, it will save you so much time debugging. It isn't always an option, especially for legacy code bases, but it is awesome when you can inspect complex code. In this example, I"m just making a couple of helper methods that dump stuff but normally I'd use something like Monolog to write to a stream that I can tail, and I can easily turn it off in production. When logging, sometimes it helps to avoid identical messages so that you can easily find the exact line number you are on, too.
So with those changes, try running this code inside of your class:
private function logMessage($message)
{
echo $message . PHP_EOL;
}
private function logVariable($variable)
{
var_dump($variable);
}
public function validateIssetEmail($email, $action = null)
{
$this->logVariable($email);
$this->logVariable($action);
$b = $this->cadastro->getIssetEmail($email);
$this->logVariable($b);
if ($action === null) {
$this->logMessage('Action was null');
if ($b > 0) {
$this->logMessage('B is greater than zero');
$this->setErro("Email already registered!");
return false;
}
$this->logMessage('B was not greater than zero');
return true;
}
$this->logMessage('Action was not null');
if ($b > 0) {
$this->logMessage('B is greater than zero');
return true;
}
$this->logMessage('B was not greater than zero');
$this->setErro("Email not registered!");
return false;
}
This should log in human-readable form every step. You should be able to walk through this and identify where your bug is. For instance, in the comments above you said that a variable was 0 in a block that was guarded by a check that guarantees that that shouldn't happen.
This is the wrong part i guess you assigned login as action so you can call cadastro class inside of the function
$cadastro = new Cadastro();
$b = $cadastro->getIssetEmail($email);
if ($action == null) {
if ($b > 0) {
$this->setErro("Email already registered!");
return false;
} else {
return true;
}
} else {
if ($b > 0) {
return true;
} else {
$this->setErro("Email not registered!");
return false;
}
}

Integer is returned instead of boolean in php

I hope you are doing great. I have a class in my project with various methods. The thing that happens is, one of the methods is supposed to return a Boolean variable. Instead. It returned the number "1" instead of false. If you could tell me where is the problem.
Thanks in advance, Cheers.
Useful pieces of my code:
Class method:
public function validatePwd($pwd1, $pwd2) {
if (strcasecmp($pwd1, $pwd2) == 0)
{
return true;
}
else
{
return false;
}
}
The script that executes it:
$check1 = $user->validatePwd($Password, $Password1);
echo $check1;
if ($user->validatePwd($Password, $Password1))
{
}
else
{
$errors[] = 'Error!, passwords entered are not compatible, Please'
. ' enter passwords that match each other';
}
If you do var_dump($check1) instead of echo $check1; it should show as boolean.

Variable to another php file

I have a php file(register.php) with a public function register($data) where errors are validated.Then errors are counted and if no errors are found, validation is passed.
register.php:
class ARegister {
public function register($data) {
$user = $data['userData'];
//validate provided data
$errors = $this->validateUser($data);
if(count($errors) == 0) {
//first validation
}
}
public function validateUser($data, $botProtection = true) {
$id = $data['fieldId'];
$user = $data['userData'];
$errors = array();
$validator = new AValidator();
if( $validator->isEmpty($user['password']) )
$errors[] = array(
"id" => $id['password'],
"msg" => Lang::get('password_required')
);
return $errors;
}
The problem is, that I need to get this confirmation of validated data to my other php file (othervalidation.php) where I've made another validation:
othervalidation.php:
<?php
require 'register.php';
if ( !empty($action) ) {
switch ( $action ) {
case 'process_payment':
try {
$instance = new ARegister();
if($instance->validateUser($data, $errors)) {
throw new Exception('Validation error');
}
} catch (Exception $e) {
$status = false;
$message = $e->getMessage();
}
}
How can I send the result of $errors variable to my other validation (othervalidation.php)?
I looked at your new code design and here's the new problems I found.
First, in your register function, you use the errors variable as an integer while your validate function returns an array. You got two possibilities here.
You can change your register method to check out if your error array is empty like this:
if(empty($errors)) {
//first validation
}
Count is also valid, but I still prefer empty since it's syntactically clearer. Furthermore, the count function returns 1 if the parameter is not an array or a countable object or 0 if the parameter is NULL. As I said, it is a functional solution in your current case but, in some other contexts, it might cause you unexpected results.
Here in your method declaration, I see that you are expecting a boolean (botProtection).
public function validateUser($data, $botProtection = true) {
But you are supplying an errors parameter
if($instance->validateUser($data, $errors)) {
You don't provide me the declaration of the errors variable, but it is probably not matching the bot protection parameter your function is expecting. PHP is using lose typing, it is useful but, once again, you got to be careful for bugs hard to find. For public function, you should always make sure a way or another that the supplied parameter won't lead to code crash.
In your code, the data parameter seems to be an array. You can use parameter hinting to force the use of array like this:
public function register(array $data) {
public function validateUser(array $data, $botProtection = true) {
And even specific class (as if you where using "instance of" in a condition)
public function register(MyDataClass $data) {
public function validateUser(MyDataClass $data, $botProtection = true) {
Also, you're not even using the botProtection parameter in your validateUser method.
On the same function call:
if($instance->validateUser($data, $errors)) {
you are expecting a Boolean (true or false), but the method returns an array. If you want to use the code the way it is currently designed, you must use it like this
if(!empty($instance->validateUser($data, $errors)) {
Here, I'm not so sure it is necessary to use exception. Ain't it be easier to design your code like this?
if(!empty($instance->validateUser($data, $errors)) {
$message = 'Validation error';
}
In your validate function, is the "isEmpty" function also validating if the client provided a password?
If that's the case you could validate it like this:
if(!in_array($user['password']) or empty($user['password']))
With those corrections, your code should be functional.
Here's a sample of how I would had design your code (considering the code sample provided):
class ARegister {
public function register($data) {
$user = $data['userData']; //don't declare it here, all the user validations must be done in validateUser($data, &$errors)
$errors = array();
if($this->validateUser($data, $errors)) {
//first validation
}
}
/**
* Note: If you are not returing more than one error at the time, $errors should be a string instead of an array.
*/
public function validateUser($data, array &$errors) {
$isValid = false;
if (in_array($data['fieldId']) and in_array($data['fieldId']['password']) and in_array($data['userData'])){
if(!in_array($data['userData']['password']) or empty($data['userData']['password'])){
$errors[$data['fieldId']['password']] = Lang::get('password_required');
}
else{
$isValid = true;
}
}
else{
//an invalid data array had been provided
}
return $isValid;
}
For the next part, if the code is executed directly in the view and you are a beginner, create a procedural external controller file (all functions will be public...). If you are a professional, you MUST create a class to encapsulate the treatment.
You must not do treatment directly in the view. The view is a dumb placeholder for data presentation and collecting client's input. The sole action it must do is display the data sent by the controller and send back the client's input to the controller.
The treatment on data is the controller responsibility.
if (!empty($action) ) {
$errors =array();
switch ( $action ) {
case 'process_payment':
$instance = new ARegister();
if($instance->validateUser($data, $errors)) {
//the user is valid, do the treatment
}
else
PageManager::dispayError($errors);
}
unset($instance);
}
}
Here's an example how you can centralize your error display
/**
* Can be more complexe than that, but I'm at my father's home at four hundred kms away from Montreal right now..
*/
public static function dispayError($errors, $size = 4){
if (is_numeric($size)){
if ($size < 0){
$size = 1;
}
elseif($size > 5){
$size = 5;
}
}
else{
$size = 4;
}
if (is_scalar($errors)){
echo '<h' . $size . 'class="ERROR_MESSAGE">' . $errors . '</h' . $size . '><br>';
}
elseif (is_array($errors)){
foreach ($errors as $error){
if (is_scalar($error)){
echo '<h' . $size . 'class="ERROR_MESSAGE">' . $error . '</h' . $size . '><br>';
}
}
}
}
Of course, you can also support many kind of message:
public static function dispayError($errors, $size = 4){
self::displayMessage("ERROR_MESSAGE", $errors, $size=4);
}
private static displayMessage($class, $messages, $size=4)
Well, took me two hours to write that. I hope you have now enough material to build an efficient, reusable and, no less important, safe code design.
Good success,
Jonathan Parent-Lévesque from Montreal
You can try something like this:
class ARegister {
private $error = 0;
public function register($data) {
if (!$this->validateUser($data)){
$this->error++;
}
}
public function getErrorCount(){
return $this->error;
}
public resetErrorCount(){
$this->error = 0;
}
Or pass the error by reference:
public function register(&$error, $data) {
if (!$this->validateUser($data)){
$error++;
}
}
Personally, I would do all the validation in the same method (in the class for encapsulation), use an error message parameter (passed by reference) to return why the validation failed and use the return statement to return true or false.
class MyClass{
public function validation(&$errorMessage, $firstParameter, $secondParameter){
$success = false;
if (!$this->firstValidation($firstParameter)){
$errorMessage = "this is not working pal.";
}
elseif (!this->secondeValidation($firstParameter)){
$errorMessage = "Still not working buddy...";
}
else{
$success = true;
}
return $success;
}
private function firstValidation($firstParameter){
$success = false;
return $success;
}
private function secondeValidation($secondParameter){
$success = false;
return $success;
}
}
In your other file:
<?php
$instance = new MyClass();
$errorMessage = "";
if ($instance->validation($errorMessage, $firstParameter, $secondParameter)){
echo "Woot, it's working!!!";
}
else{
echo $errorMessage;
}
?>
Is one of these code solutions fit your needs?
Jonathan Parent-Lévesque from Montreal

jquery & php + if session is dead an error is returned

I've noticed if the session is dead (on an Jquery AJAX PHP Request) the data returned is preceeded with an error message if the session is needed in the request.
How do other sites deal with this?
Similar code is shown below - eg: its using a SESSION variable in the code which doesn't exist as the session is dead.
public function internal($variable) {
if($_SESSION['data'] == $variable) {
echo TRUE;
}else{
echo FALSE;
}
}
Should I use isset to check if the variable exists?
Should I be coding for dead sessions?
thx
You need to add the isset also:
public function internal($variable) {
if(isset($_SESSION['data']) && $_SESSION['data'] == $variable) { //add here
echo TRUE;
}else{
echo FALSE;
}
}
Try this
public function internal($variable) {
if($_SESSION['data']!="" && $_SESSION['data'] == $variable) { //add here
echo TRUE;
}else{
echo FALSE;
}
}
You can also do like this,
public function internal($variable) {
if(!empty($_SESSION['data']) && $_SESSION['data'] == $variable) { // modify here
echo TRUE;
}else{
echo FALSE;
}
}

PHP function not working

<?php
$name = $_POST['name'];
$namecheck = namecheck($name);
function namecheck($name){
if(strlen($name)>0)
{
return TRUE;
}
else if(strlen($name)==0)
{
return FALSE;
}
};
function control($namecheck1)
{
if ($namecheck == TRUE)
{
echo "It is TRUE";
}
else if ($namecheck == FALSE)
{
echo "It is FALSE";
}
};
?>
I wrote that there is no problem in HTML part, there is a problem in my php functions because I am new in PHP. Can you make it proper.
I think you will understand what I want to do in the functions its simple Im trying to do if it is true I want to see "it is TRUE" in the screen. Else .....
Take a look at the variables. They don't match:
function control($namecheck1)
{
if ($namecheck == TRUE)
You also never actually invoke that function.
You're not calling your 'control' function. try starting with
$name = $_POST['name'];
$namecheck = namecheck($name);
control($namecheck);
Also, your definition of you function is wrong (or the variable you use is). You can change the function to this
function control($namecheck)
Of the if's to
if ($namecheck1 == TRUE)
in the end the name after control( is the one you should check for in the if's
In your control function, the parameter is called $namecheck1 at first, but you only call it $namecheck when you try to use it inside the function.
It looks as if you are not calling control function.
your are referencing $namecheck in the function "control" but the parameter passed is named $namecheck1. $namecheck in the scope of function "control" is undefined.
Some tips:
instead namecheck() you can use empty()
before using $_POST['name'] you should check if it exists isset() should help
This works fine
<?php
$name = $_REQUEST['name'];
function namecheck($name1)
{
if(!empty($name1))
{
return TRUE;
}
else
{
return FALSE;
}
}
if (namecheck($name) == TRUE)
{
echo "It is TRUE";
}
else if (namecheck($name) == FALSE)
{
echo "It is FALSE";
}
?>

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