Getting an array result from json_decode
How do I get an array as a result from json_decode()
?
I had an array like this:
$array = array(
'mod_status' => 'yes',
'mod_newsnum' => 5
);
and I saved 开发者_高级运维this in database like JSON encode:
{"mod_status":"yes","mod_newsnum":5}
Now I want to get array again from database. But when i use:
$decode = json_decode($dbresult);
I get:
stdClass Object (
[mod_status] => yes
[mod_newsnum] => 5
)
Instead of an array. How can I get an array instead of an object?
Set the second parameter of json_decode
to true to force associative arrays:
$decode = json_decode($dbresult, true);
As per http://in3.php.net/json_decode:
$decode = json_decode($dbresult, TRUE);
$decode = json_decode($dbresult, true);
Or
$decode = (array)json_decode($dbresult);
Casting the object result of json_decode
to an array can have unexpected results (and cause headaches). Because of this, it is recommended to use json_decode($json, true)
instead of (array)json_decode($json)
. Here is an example:
Broken:
<?php
$json = '{"14":"29","15":"30"}';
$data = json_decode($json);
$data = (array)$data;
// Array ( [14] => 29 [15] => 30 )
print_r($data);
// Array ( [0] => 14 [1] => 15 )
print_r(array_keys($data));
// all of these fail
echo $data["14"];
echo $data[14];
echo $data['14'];
// this also fails
foreach(array_keys($data) as $key) {
echo $data[$key];
}
Working:
<?php
$json = '{"14":"29","15":"30"}';
$data = json_decode($json, true);
// Array ( [14] => 29 [15] => 30 )
print_r($data);
// Array ( [0] => 14 [1] => 15 )
print_r(array_keys($data));
// all of these work
echo $data["14"];
echo $data[14];
echo $data['14'];
// this also works
foreach(array_keys($data) as $key) {
echo $data[$key];
}
If you only use that data in PHP I recommend using serialize
and unserialize
instead or else you'll never be able to differentiate between objects and associative arrays, because the object class information is lost when encoding to JSON.
<?php
class myClass{// this information will be lost when JSON encoding //
public function myMethod(){
echo 'Hello there!';
}
}
$x = array('a'=>1, 'b'=>2);
$y = new myClass;
$y->a = 1;
$y->b = 2;
echo json_encode($x), "\n", json_encode($y); // identical
echo "\n", serialize($x), "\n", serialize($y); // not identical
?>
Run it.
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