hoping you can help me out with this question!
Index.php
include_once 'files.class.php';
$file_object = new FileObject('resources');
$file_object->ReturnCurrentDirectoryList();
files.class.php
class FileObject{
public $directory_list;
function __construct($current_directory_in){
$this->directory_list = $this->BuildCurrentDirectoryList($current_directory_in);
}
function BuildCurrentDirectoryList($current_directory_in){
$i = 0;
$iterator = new DirectoryIterator($current_directory_in);
foreach ($iterator as $fileinfo){
if ($fileinfo->isDir()){
$this->directory_list[$i]['pathname'] = $fileinfo->getPathname();
}elseif($fileinfo->isFile()){
$this->directory_list[$i]['filename'] = $fileinfo->getFilename();
}
$i++;
}
}
function ReturnCurrentDirectoryList(){
var_dump($this->directory_list);
}
}
At the end of all this, what is returned is
null
but what should be returned is
array 0 => array 'pathname' => string 'resources\.', 1 => array 'pathname' => string 'resources\..', 2 => array 'pathname' => string 'resources\Images'
I'm somewhat new to classes/methods..
This is wrong:
$this->directory_list = $this->BuildCurrentDirectoryList($current_directory_in);
You assign to $this->directory_list but BuildCurrentDirectoryList does not return anything. The function have side-effects only, no return value.
Remove the assignment so the constructor looks like this and you should be good to go:
$this->directory_list = array(); //I like to initialise arrays to the empty array
$this->BuildCurrentDirectoryList($current_directory_in);
In your constructor, you are assigning directory_list to the return of BuildCurrentDirectoryList, but you are not returning nothing in BuildCurrentDirectoryList, you are assigning directory_list directly in that method. At the end, BuildCurrentDirectoryList returns NULL. So, either return the directory_list, or else just don't assign it like this:
function __construct($current_directory_in){
$this->BuildCurrentDirectoryList($current_directory_in);
}
Related
I've a function which returns an array. To return the value of that array I do something like this:
$obj->methodname()[keyvalue];
This works in php 5.4 only. I want to make this code work in lower php versions.
My code:
class ObjectTest {
public $ar;
function __construct() {
$this->ar = array(
1 => 'beeldscherm',
2 => 'geluidsbox',
3 => 'toetsenbord',);
}
public function arr(){
return $this->ar;
}
}
$obj = new ObjectTest();
//by calling the method and putting square brackets and the key of the element
var_dump($obj->arr()[2]);
I've rewritten the code for lower versions like this:
public function arr($arg = null){
if(is_null($arg)){
return $this->ar;
}
return $this->ar[$arg];
}
I'm doubting if this solution is an elegant one. What would you say? Any better solutions?
You can do like, store array in a variable and than access particular array index.
$arrList = var_dump($obj->arr());
echo $arrList[2];
I want to make a foreach loop like this one
foreach ($this->data['array'] as $this->data['key'] => $this->data['value'])
{
echo $this->data['value'];
}
Yet the $this->data['value'] is never created. Why is this and what am I doing wrong?
In my understanding, you have a class in which there is a variable or array name $data.
Now, you added an array in $data with an index named 'array', right?
If so, this code will work properly -
class myClass{
public $data = array(); //$data is an array
function print_array(){
foreach ($this->data['array'] as $this->data['key'] => $this->data['value'])
{
echo $this->data['value'];
}
}
}
$ob = new myClass(); // object declaration for your class
array_push($ob->data,'array'); // added a value to the $data array.
$ob->data['array'] = array(); // the newly added value is declared as an index of an array
// Now simply push values to the array named $data['array']
array_push($ob->data['array'],1);
array_push($ob->data['array'],2);
array_push($ob->data['array'],3);
$ob->print_array(); // call the print_array() function. $this will be passed to that function
Hope this will help to understand.
If you still have problem, please comment.
To have a clear understanding, you can visit this link. There are lots of simple and interesting examples explained!
Happy Coding!
I think $this is for current class object reference not for an array
foreach ($this->data['array'] as $k => $v)
{
echo $v;
$this->data['key'][] = $k;
$this->data['value'][] = $v;
}
print_r($this->data['key']);
print_r($this->data['value']);
If:
class YourClass {
private data = array(
'array' => array(
'key1' => 'val1',
'key2' => 'val2', etc.
)
);
then it should be:
foreach ($this->data['array'] as $key => $val)
{
echo $val;
// if you want to add keys and vals to data array:
$this->data[$key] = $val;
}
Is it possible to set multiple properties at a time for an object in php?
Instead of doing:
$object->prop1 = $something;
$object->prop2 = $otherthing;
$object->prop3 = $morethings;
do something like:
$object = (object) array(
'prop1' => $something,
'prop2' => $otherthing,
'prop3' => $morethings
);
but without overwriting the object.
Not like the way you want. but this can be done by using a loop.
$map = array(
'prop1' => $something,
'prop2' => $otherthing,
'prop3' => $morethings
);
foreach($map as $k => $v)
$object->$k = $v;
See only 2 extra lines.
You should look at Object Oriented PHP Best Practices :
"since the setter functions return $this you can chain them like so:"
$object->setName('Bob')
->setHairColor('green')
->setAddress('someplace');
This incidentally is known as a fluent interface.
I would recommend you don't do it. Seriously, don't.
Your code is much MUCH cleaner the first way, it's clearer of your intentions, and you aren't obfocusing your code to the extent where sometime in the future someone would look at your code and think "What the hell was the idiot thinking"?
If you insist on doing something which is clearly the wrong way to go, you can always create an array, iterate it and set all the properties in a loop. I won't give you code though. It's evil.
You could write some setters for the object that return the object:
public function setSomething($something)
{
$this->something = $something;
return $this; //this will return the current object
}
You could then do:
$object->setSomething("something")
->setSomethingelse("somethingelse")
->setMoreThings("some more things");
You would need to write a setter for each property as a __set function is not capable of returning a value.
Alternatively, set a single function to accept an array of property => values and set everything?
public function setProperties($array)
{
foreach($array as $property => $value)
{
$this->{$property} = $value;
}
return $this;
}
and pass in the array:
$object->setProperties(array('something' => 'someText', 'somethingElse' => 'more text', 'moreThings'=>'a lot more text'));
I realise this is an old question but for the benefit of others that come across it, I solved this myself recently and wanted to share the result
<?php
//Just some setup
header('Content-Type: text/plain');
$account = (object) array(
'email' => 'foo',
'dob'=>((object)array(
'day'=>1,
'month'=>1,
'year'=>((object)array('century'=>1900,'decade'=>0))
))
);
var_dump($account);
echo "\n\n==============\n\n";
//The functions
function &getObjRef(&$obj,$prop) {
return $obj->{$prop};
}
function updateObjFromArray(&$obj,$array){
foreach ($array as $key=>$value) {
if(!is_array($value))
$obj->{$key} = $value;
else{
$ref = getObjRef($obj,$key);
updateObjFromArray($ref,$value);
}
}
}
//Test
updateObjFromArray($account,array(
'id' => '123',
'email' => 'user#domain.com',
'dob'=>array(
'day'=>19,
'month'=>11,
'year'=>array('century'=>1900,'decade'=>80)
)
));
var_dump($account);
Obviously there are no safeguards built in. The main caveat is that the updateObjFromArray function assumes that for any nested arrays within $array, the corresponding key in $obj already exists and is an object, this must be true or treating it like an object will throw an error.
Hope this helps! :)
I wouldn't actually do this....but for fun I would
$object = (object) ($props + (array) $object);
you end up with an stdClass composed of $objects public properties, so it loses its type.
Method objectThis() to transtypage class array properties or array to stdClass. Using direct transtypage (object) would remove numeric index, but using this method it will keep the numeric index.
public function objectThis($array = null) {
if (!$array) {
foreach ($this as $property_name => $property_values) {
if (is_array($property_values) && !empty($property_values)) {
$this->{$property_name} = $this->objectThis($property_values);
} else if (is_array($property_values) && empty($property_values)) {
$this->{$property_name} = new stdClass();
}
}
} else {
$object = new stdClass();
foreach ($array as $index => $values) {
if (is_array($values) && empty($values)) {
$object->{$index} = new stdClass();
} else if (is_array($values)) {
$object->{$index} = $this->objectThis($values);
} else if (is_object($values)) {
$object->{$index} = $this->objectThis($values);
} else {
$object->{$index} = $values;
}
}
return $object;
}
}
All my AJAX requests are in json format which are being parsed in javascript.
How can i prevent null values being displayed in an HTML page without needing to write an if-statement in javascript for each json value?
Or should i write a custom PHP function to encode an array to json instead of using json_encode() so it doesn't display 'null' ?
In server side with PHP,
You can use array_filter before json_encode.
array_filter without second argument removes null elements of entry array, example :
$object= array(
0 => 'foo',
1 => false,
2 => -1,
3 => null,
4 => ''
);
$object = (object) array_filter((array) $object);
$result = json_encode($object);
The $result contains:
{"0":"foo","2":-1}
As you see, the null elements are removed.
I'm going to add to the accepted answer because that will only work if you have a 1 dimensional object or array. If there is any array or object nesting then in order to get the accepted solution to work, you must create some sort of recursive array filter. Not ideal.
The best solution my colleague and I came up with was to actually perform a regular expression on the JSON string before it was returned from the server.
$json = json_encode($complexObject);
echo preg_replace('/,\s*"[^"]+":null|"[^"]+":null,?/', '', $json);
The regular expression will remove all places in the string of the form ,"key":null including any whitespace between the leading comma and the start of the key. It will also match "key":null, afterwards to make sure that no null values were found at the beginning of a JSON object.
This isn't an ideal solution but it's far better than creating a recursive array filter given an object could be several dimensions deep. A better solution would be if json_encode had a flag that let you specify if you wanted null entries to remain in the output string.
To remove only NULL, but keep FALSE, '', and 0:
function is_not_null($var)
{
return !is_null($var);
}
echo json_encode(array_filter((array) $object, 'is_not_null'));
public function __toString() {
$obj = clone $this;
$keys = get_object_vars($obj);
foreach ($keys as $key => $value) {
if (!$value) {
unset($obj->{$key});
}
}
return json_encode($obj);
}
What about using the native JSON.stringify method on the javascript side?
You can set, a second parameter, a function to remove keys with a null value.
If you return undefined, the property is not included in the output JSON string (check the documentation for "the replacer parameter" at https://developer.mozilla.org/en-US/docs/Using_native_JSON#The_replacer_parameter).
function removeNulls(obj) {
var str = JSON.stringify(obj, function(key, val) {
if (val == null) return undefined;
return val;
});
return JSON.parse(str);
}
Then you can have a "normalized" JSON object by calling:
var obj = removeNulls(obj);
echo json_encode(array_filter((array) $object, function($val) {
return !empty($val);
}));
class Foo implements JsonSerializable
{
public $param1;
public $param2;
public function jsonSerialize()
{
return array_filter((array) $this, function ($var) {
return !is_null($var);
});
}
}
public function testJsonSerialization()
{
$expectedJson = '{"param1":true}';
$foo = new Foo();
$foo->param1 = true;
$foo->param2 = null;
$this->assertEquals(
$expectedJson,
json_encode($foo)
);
}`
of course you can create Abstract class with custom jsonSerialize method and extend all your DTOs from this
A version that works with multi-dimensional arrays.
$withoutNull = function($a) use (&$withoutNull) {
return array_filter(
array_map(
fn($p) => is_array($p) ? $withoutNull($p) : $p, $a
)
);
};
Example:
$a = [
"name" => "nathan",
"data" => [
"age" => 27,
"something" => null
],
"another" => null
];
$b = $withoutNull($a);
print_r($b);
Output:
Array
(
[name] => nathan
[data] => Array
(
[age] => 27
)
)
I get a strange error using json_decode(). It decode correctly the data (I saw it using print_r), but when I try to access to info inside the array I get:
Fatal error: Cannot use object of type stdClass as array in
C:\Users\Dail\software\abs.php on line 108
I only tried to do: $result['context'] where $result has the data returned by json_decode()
How can I read values inside this array?
Use the second parameter of json_decode to make it return an array:
$result = json_decode($data, true);
The function json_decode() returns an object by default.
You can access the data like this:
var_dump($result->context);
If you have identifiers like from-date (the hyphen would cause a PHP error when using the above method) you have to write:
var_dump($result->{'from-date'});
If you want an array you can do something like this:
$result = json_decode($json, true);
Or cast the object to an array:
$result = (array) json_decode($json);
You must access it using -> since its an object.
Change your code from:
$result['context'];
To:
$result->context;
Use true as the second parameter to json_decode. This will decode the json into an associative array instead of stdObject instances:
$my_array = json_decode($my_json, true);
See the documentation for more details.
Have same problem today, solved like this:
If you call json_decode($somestring) you will get an Object and you need to access like $object->key , but if u call json_decode($somestring, true) you will get an dictionary and can access like $array['key']
It's not an array, it's an object of type stdClass.
You can access it like this:
echo $oResult->context;
More info here: What is stdClass in PHP?
As the Php Manual say,
print_r — Prints human-readable information about a variable
When we use json_decode();, we get an object of type stdClass as return type.
The arguments, which are to be passed inside of print_r() should either be an array or a string. Hence, we cannot pass an object inside of print_r(). I found 2 ways to deal with this.
Cast the object to array.
This can be achieved as follows.
$a = (array)$object;
By accessing the key of the Object
As mentioned earlier, when you use json_decode(); function, it returns an Object of stdClass. you can access the elements of the object with the help of -> Operator.
$value = $object->key;
One, can also use multiple keys to extract the sub elements incase if the object has nested arrays.
$value = $object->key1->key2->key3...;
Their are other options to print_r() as well, like var_dump(); and var_export();
P.S : Also, If you set the second parameter of the json_decode(); to true, it will automatically convert the object to an array();
Here are some references:
http://php.net/manual/en/function.print-r.php
http://php.net/manual/en/function.var-dump.php
http://php.net/manual/en/function.var-export.php
Try something like this one!
Instead of getting the context like:(this works for getting array index's)
$result['context']
try (this work for getting objects)
$result->context
Other Example is: (if $result has multiple data values)
Array
(
[0] => stdClass Object
(
[id] => 15
[name] => 1 Pc Meal
[context] => 5
[restaurant_id] => 2
[items] =>
[details] => 1 Thigh (or 2 Drums) along with Taters
[nutrition_fact] => {"":""}
[servings] => menu
[availability] => 1
[has_discount] => {"menu":0}
[price] => {"menu":"8.03"}
[discounted_price] => {"menu":""}
[thumbnail] => YPenWSkFZm2BrJT4637o.jpg
[slug] => 1-pc-meal
[created_at] => 1612290600
[updated_at] => 1612463400
)
)
Then try this:
foreach($result as $results)
{
$results->context;
}
To get an array as result from a json string you should set second param as boolean true.
$result = json_decode($json_string, true);
$context = $result['context'];
Otherwise $result will be an std object. but you can access values as object.
$result = json_decode($json_string);
$context = $result->context;
Sometimes when working with API you simply want to keep an object an object. To access the object that has nested objects you could do the following:
We will assume when you print_r the object you might see this:
print_r($response);
stdClass object
(
[status] => success
[message] => Some message from the data
[0] => stdClass object
(
[first] => Robert
[last] => Saylor
[title] => Symfony Developer
)
[1] => stdClass object
(
[country] => USA
)
)
To access the first part of the object:
print $response->{'status'};
And that would output "success"
Now let's key the other parts:
$first = $response->{0}->{'first'};
print "First name: {$first}<br>";
The expected output would be "Robert" with a line break.
You can also re-assign part of the object to another object.
$contact = $response->{0};
print "First Name: " . $contact->{'first'} . "<br>";
The expected output would be "Robert" with a line break.
To access the next key "1" the process is the same.
print "Country: " . $response->{1}->{'country'} . "<br>";
The expected output would be "USA"
Hopefully this will help you understand objects and why we want to keep an object an object. You should not need to convert an object to an array to access its properties.
You can convert stdClass object to array like:
$array = (array)$stdClass;
stdClsss to array
When you try to access it as $result['context'], you treating it as an array, the error it's telling you that you are actually dealing with an object, then you should access it as $result->context
Here is the function signature:
mixed json_decode ( string $json [, bool $assoc = false [, int $depth = 512 [, int $options = 0 ]]] )
When param is false, which is default, it will return an appropriate php type. You fetch the value of that type using object.method paradigm.
When param is true, it will return associative arrays.
It will return NULL on error.
If you want to fetch value through array, set assoc to true.
I got this error out of the blue because my facebook login suddently stopped working (I had also changed hosts) and throwed this error. The fix is really easy
The issue was in this code
$response = (new FacebookRequest(
FacebookSession::newAppSession($this->appId, $this->appSecret),
'GET',
'/oauth/access_token',
$params
))->execute()->getResponse(true);
if (isset($response['access_token'])) { <---- this line gave error
return new FacebookSession($response['access_token']);
}
Basically isset() function expect an array but instead it find an object. The simple solution is to convert PHP object to array using (array) quantifier. The following is the fixed code.
$response = (array) (new FacebookRequest(
FacebookSession::newAppSession($this->appId, $this->appSecret),
'GET',
'/oauth/access_token',
$params
))->execute()->getResponse(true);
Note the use off array() quantifier in first line.
instead of using the brackets use the object operator for example my array based on database object is created like this in a class called DB:
class DB {
private static $_instance = null;
private $_pdo,
$_query,
$_error = false,
$_results,
$_count = 0;
private function __construct() {
try{
$this->_pdo = new PDO('mysql:host=' . Config::get('mysql/host') .';dbname=' . Config::get('mysql/db') , Config::get('mysql/username') ,Config::get('mysql/password') );
} catch(PDOException $e) {
$this->_error = true;
$newsMessage = 'Sorry. Database is off line';
$pagetitle = 'Teknikal Tim - Database Error';
$pagedescription = 'Teknikal Tim Database Error page';
include_once 'dbdown.html.php';
exit;
}
$headerinc = 'header.html.php';
}
public static function getInstance() {
if(!isset(self::$_instance)) {
self::$_instance = new DB();
}
return self::$_instance;
}
public function query($sql, $params = array()) {
$this->_error = false;
if($this->_query = $this->_pdo->prepare($sql)) {
$x = 1;
if(count($params)) {
foreach($params as $param){
$this->_query->bindValue($x, $param);
$x++;
}
}
}
if($this->_query->execute()) {
$this->_results = $this->_query->fetchAll(PDO::FETCH_OBJ);
$this->_count = $this->_query->rowCount();
}
else{
$this->_error = true;
}
return $this;
}
public function action($action, $table, $where = array()) {
if(count($where) ===3) {
$operators = array('=', '>', '<', '>=', '<=');
$field = $where[0];
$operator = $where[1];
$value = $where[2];
if(in_array($operator, $operators)) {
$sql = "{$action} FROM {$table} WHERE {$field} = ?";
if(!$this->query($sql, array($value))->error()) {
return $this;
}
}
}
return false;
}
public function get($table, $where) {
return $this->action('SELECT *', $table, $where);
public function results() {
return $this->_results;
}
public function first() {
return $this->_results[0];
}
public function count() {
return $this->_count;
}
}
to access the information I use this code on the controller script:
<?php
$pagetitle = 'Teknikal Tim - Service Call Reservation';
$pagedescription = 'Teknikal Tim Sevice Call Reservation Page';
require_once $_SERVER['DOCUMENT_ROOT'] .'/core/init.php';
$newsMessage = 'temp message';
$servicecallsdb = DB::getInstance()->get('tt_service_calls', array('UserID',
'=','$_SESSION['UserID']));
if(!$servicecallsdb) {
// $servicecalls[] = array('ID'=>'','ServiceCallDescription'=>'No Service Calls');
} else {
$servicecalls = $servicecallsdb->results();
}
include 'servicecalls.html.php';
?>
then to display the information I check to see if servicecalls has been set and has a count greater than 0 remember it's not an array I am referencing so I access the records with the object operator "->" like this:
<?php include $_SERVER['DOCUMENT_ROOT'] .'/includes/header.html.php';?>
<!--Main content-->
<div id="mainholder"> <!-- div so that page footer can have a minum height from the
header -->
<h1><?php if(isset($pagetitle)) htmlout($pagetitle);?></h1>
<br>
<br>
<article>
<h2></h2>
</article>
<?php
if (isset($servicecalls)) {
if (count ($servicecalls) > 0){
foreach ($servicecalls as $servicecall) {
echo '<a href="/servicecalls/?servicecall=' .$servicecall->ID .'">'
.$servicecall->ServiceCallDescription .'</a>';
}
}else echo 'No service Calls';
}
?>
Raise New Service Call
</div> <!-- Main content end-->
<?php include $_SERVER['DOCUMENT_ROOT'] .'/includes/footer.html.php'; ?>
It is most likely when it tries to access the data with the generic bracket array accessor and not an object operator. Always ensure the variable type is before accessing the data.
While decoding the JSON, the response will be generated as stdObject instances
Rather than calling $result['context'];, access it by $result->context;
If it needs to call as an array itself, decode the JSON by passing the second parameter as true like
json_decode($jsonData, true);
Change it for
$results->fetch_array()