问题
I'm trying to output lists of objects as json and would like to know if there's a way to make objects usable to json_encode? The code I've got looks something like
$related = $user->getRelatedUsers();
echo json_encode($related);
Right now, I'm just iterating through the array of users and individually exporting them into arrays for json_encode to turn into usable json for me. I've already tried making the objects iterable, but json_encode just seems to skip them anyway.
edit: here's the var_dump();
php > var_dump($a);
object(RedBean_OODBBean)#14 (2) {
["properties":"RedBean_OODBBean":private]=>
array(11) {
["id"]=>
string(5) "17972"
["pk_UniversalID"]=>
string(5) "18830"
["UniversalIdentity"]=>
string(1) "1"
["UniversalUserName"]=>
string(9) "showforce"
["UniversalPassword"]=>
string(32) ""
["UniversalDomain"]=>
string(1) "0"
["UniversalCrunchBase"]=>
string(1) "0"
["isApproved"]=>
string(1) "0"
["accountHash"]=>
string(32) ""
["CurrentEvent"]=>
string(4) "1204"
["userType"]=>
string(7) "company"
}
["__info":"RedBean_OODBBean":private]=>
array(4) {
["type"]=>
string(4) "user"
["sys"]=>
array(1) {
["idfield"]=>
string(2) "id"
}
["tainted"]=>
bool(false)
["model"]=>
object(Model_User)#16 (1) {
["bean":protected]=>
*RECURSION*
}
}
}
and here's what json_encode gives me:
php > echo json_encode($a);
{}
I ended up with just this:
function json_encode_objs($item){
if(!is_array($item) && !is_object($item)){
return json_encode($item);
}else{
$pieces = array();
foreach($item as $k=>$v){
$pieces[] = "\"$k\":".json_encode_objs($v);
}
return '{'.implode(',',$pieces).'}';
}
}
It takes arrays full of those objects or just single instances and turns them into json - I use it instead of json_encode. I'm sure there are places I could make it better, but I was hoping that json_encode would be able to detect when to iterate through an object based on its exposed interfaces.
回答1:
In RedBeanPHP 2.0 there is a mass-export function which turns an entire collection of beans into arrays. This works with the JSON encoder..
json_encode( R::exportAll( $beans ) );
回答2:
All the properties of your object are private. aka... not available outside their class's scope.
Solution for PHP < 5.4
If you do want to serialize your private and protected object properties, you have to implement a JSON encoding function inside your Class that utilizes json_encode() on a data structure you create for this purpose.
class Thing {
...
public function to_json() {
return json_encode(array(
'something' => $this->something,
'protected_something' => $this->get_protected_something(),
'private_something' => $this->get_private_something()
));
}
...
}
Solution for PHP >= 5.4
Use the new JsonSerializable Interface to provide your own json representation to be used by json_encode
class Thing implements JsonSerializable {
...
public function jsonSerialize() {
return [
'something' => $this->something,
'protected_something' => $this->get_protected_something(),
'private_something' => $this->get_private_something()
];
}
...
}
A more detailed writeup
回答3:
In PHP >= 5.4.0 there is a new interface for serializing objects to JSON : JsonSerializable
Just implement the interface in your object and define a JsonSerializable method which will be called when you use json_encode.
So the solution for PHP >= 5.4.0 should look something like this:
class JsonObject implements JsonSerializable
{
// properties
// function called when encoded with json_encode
public function jsonSerialize()
{
return get_object_vars($this);
}
}
回答4:
Following code worked for me:
public function jsonSerialize()
{
return get_object_vars($this);
}
回答5:
I didn't see this mentioned yet, but beans have a built-in method called getProperties().
So, to use it:
// What bean do we want to get?
$type = 'book';
$id = 13;
// Load the bean
$post = R::load($type,$id);
// Get the properties
$props = $post->getProperties();
// Print the JSON-encoded value
print json_encode($props);
This outputs:
{
"id": "13",
"title": "Oliver Twist",
"author": "Charles Dickens"
}
Now take it a step further. If we have an array of beans...
// An array of beans (just an example)
$series = array($post,$post,$post);
...then we could do the following:
Loop through the array with a
foreachloop.Replace each element (a bean) with an array of the bean's properties.
So this...
foreach ($series as &$val) {
$val = $val->getProperties();
}
print json_encode($series);
...outputs this:
[
{
"id": "13",
"title": "Oliver Twist",
"author": "Charles Dickens"
},
{
"id": "13",
"title": "Oliver Twist",
"author": "Charles Dickens"
},
{
"id": "13",
"title": "Oliver Twist",
"author": "Charles Dickens"
}
]
Hope this helps!
回答6:
I usually include a small function in my objects which allows me to dump to array or json or xml. Something like:
public function exportObj($method = 'a')
{
if($method == 'j')
{
return json_encode(get_object_vars($this));
}
else
{
return get_object_vars($this);
}
}
either way, get_object_vars() is probably useful to you.
回答7:
$products=R::findAll('products');
$string = rtrim(implode(',', $products), ',');
echo $string;
回答8:
Here is my way:
function xml2array($xml_data)
{
$xml_to_array = [];
if(isset($xml_data))
{
if(is_iterable($xml_data))
{
foreach($xml_data as $key => $value)
{
if(is_object($value))
{
if(empty((array)$value))
{
$value = (string)$value;
}
else
{
$value = (array)$value;
}
$value = xml2array($value);
}
$xml_to_array[$key] = $value;
}
}
else
{
$xml_to_array = $xml_data;
}
}
return $xml_to_array;
}
回答9:
for an array of objects, I used something like this, while following the custom method for php < 5.4:
$jsArray=array();
//transaction is an array of the class transaction
//which implements the method to_json
foreach($transactions as $tran)
{
$jsArray[]=$tran->to_json();
}
echo json_encode($jsArray);
来源：https://stackoverflow.com/questions/4697656/using-json-encode-on-objects-in-php-regardless-of-scope