Browsers don't choke on integers _starting_ with BigInt (64 bits), but before that (53 bits). The introduction of BigInt to modern browsers doesn't help much, when JSON handling functions do not support it. So I am trying to remedy that. My approach is to handle the decoded array before re-encoding it to a string:
<?php
function fix_large_int(&$value)
{
if (is_int($value) && $value > 9007199254740991)
$value = strval($value);
}
$json_str = '{"id":[1234567890123456789,12345678901234567890]}';
$json_arr = json_decode($json_str, flags: JSON_BIGINT_AS_STRING | JSON_OBJECT_AS_ARRAY);
echo(json_encode($json_arr)); // {"id":[1234567890123456789,"12345678901234567890"]} (BigInt is already converted to a string here)
array_walk_recursive($json_arr, 'fix_large_int');
echo(json_encode($json_arr)); // {"id":["1234567890123456789","12345678901234567890"]}
?>
json_decode
(PHP 5 >= 5.2.0, PECL json >= 1.2.0)
json_decode — Decodes a JSON string
說明
mixed json_decode
( string
$json
[, bool $assoc = false
[, int $depth = 512
[, int $options = 0
]]] )Takes a JSON encoded string and converts it into a PHP variable.
參數
-
json -
The
jsonstring being decoded.This function only works with UTF-8 encoded strings.
Note:
PHP implements a superset of JSON - it will also encode and decode scalar types and
NULL. The JSON standard only supports these values when they are nested inside an array or an object. -
assoc -
When
TRUE, returned objects will be converted into associative arrays. -
depth -
User specified recursion depth.
-
options -
Bitmask of JSON decode options. Currently only
JSON_BIGINT_AS_STRINGis supported (default is to cast large integers as floats)
回傳值
Returns the value encoded in json in appropriate
PHP type. Values true, false and
null are returned as TRUE, FALSE and NULL
respectively. NULL is returned if the json cannot
be decoded or if the encoded data is deeper than the recursion limit.
範例
Example #1 json_decode() examples
<?php
$json = '{"a":1,"b":2,"c":3,"d":4,"e":5}';
var_dump(json_decode($json));
var_dump(json_decode($json, true));
?>
上例將輸出：
object(stdClass)#1 (5) {
["a"] => int(1)
["b"] => int(2)
["c"] => int(3)
["d"] => int(4)
["e"] => int(5)
}
array(5) {
["a"] => int(1)
["b"] => int(2)
["c"] => int(3)
["d"] => int(4)
["e"] => int(5)
}
Example #2 Accessing invalid object properties
Accessing elements within an object that contain characters not permitted under PHP's naming convention (e.g. the hyphen) can be accomplished by encapsulating the element name within braces and the apostrophe.
<?php
$json = '{"foo-bar": 12345}';
$obj = json_decode($json);
print $obj->{'foo-bar'}; // 12345
?>
Example #3 common mistakes using json_decode()
<?php
// the following strings are valid JavaScript but not valid JSON
// the name and value must be enclosed in double quotes
// single quotes are not valid
$bad_json = "{ 'bar': 'baz' }";
json_decode($bad_json); // null
// the name must be enclosed in double quotes
$bad_json = '{ bar: "baz" }';
json_decode($bad_json); // null
// trailing commas are not allowed
$bad_json = '{ bar: "baz", }';
json_decode($bad_json); // null
?>
Example #4 depth errors
<?php
// Encode the data.
$json = json_encode(
array(
1 => array(
'English' => array(
'One',
'January'
),
'French' => array(
'Une',
'Janvier'
)
)
)
);
// Define the errors.
$constants = get_defined_constants(true);
$json_errors = array();
foreach ($constants["json"] as $name => $value) {
if (!strncmp($name, "JSON_ERROR_", 11)) {
$json_errors[$value] = $name;
}
}
// Show the errors for different depths.
foreach (range(4, 3, -1) as $depth) {
var_dump(json_decode($json, true, $depth));
echo 'Last error: ', $json_errors[json_last_error()], PHP_EOL, PHP_EOL;
}
?>
上例將輸出：
array(1) {
[1]=>
array(2) {
["English"]=>
array(2) {
[0]=>
string(3) "One"
[1]=>
string(7) "January"
}
["French"]=>
array(2) {
[0]=>
string(3) "Une"
[1]=>
string(7) "Janvier"
}
}
}
Last error: JSON_ERROR_NONE
NULL
Last error: JSON_ERROR_DEPTH
Example #5 json_decode() of large integers
<?php
$json = '{"number": 12345678901234567890}';
var_dump(json_decode($json));
var_dump(json_decode($json, false, 512, JSON_BIGINT_AS_STRING));
?>
上例將輸出：
object(stdClass)#1 (1) {
["number"]=>
float(1.2345678901235E+19)
}
object(stdClass)#1 (1) {
["number"]=>
string(20) "12345678901234567890"
}
註釋
Note:
The JSON spec is not JavaScript, but a subset of JavaScript.
Note:
In the event of a failure to decode, json_last_error() can be used to determine the exact nature of the error.
更新日誌
| 版本 | 說明 |
|---|---|
| 5.6.0 | Invalid non-lowercased variants of the true, false and null literals are no longer accepted as valid input, and will generate warnings. |
| 5.4.0 |
The options parameter was added.
|
| 5.3.0 | Added the optional depth. The default recursion depth was increased from 128 to 512 |
| 5.2.3 | The nesting limit was increased from 20 to 128 |
| 5.2.1 | Added support for JSON decoding of basic types. |
參見
- json_encode() - Returns the JSON representation of a value
- json_last_error() - Returns the last error occurred
add a note
User Contributed Notes 4 notes
Alien426 ¶
3 years ago
greaties at ghvernuft dot nl ¶
3 years ago
To load an object with data in json format:
function loadJSON($Obj, $json)
{
$dcod = json_decode($json);
$prop = get_object_vars ( $dcod );
foreach($prop as $key => $lock)
{
if(property_exists ( $Obj , $key ))
{
if(is_object($dcod->$key))
{
loadJSON($Obj->$key, json_encode($dcod->$key));
}
else
{
$Obj->$key = $dcod->$key;
}
}
}
}
cubefox at web dot NOSPAMPLEASE dot de ¶
3 years ago
Warning: As the section "return values" mentions, the return value NULL is ambiguos. To repeat, it can mean three things:
* The input string had the value "null"
* There was an error while parsing the input data
* The encoded data was deeper than the recursion limit
To distinguish these cases, json_last_error() can be used.
mattia ¶
3 years ago
if you're using ajax to post, and your JavaScript code looks like this:
<code>
var xhttp = new XMLHttpRequest();
xhttp.open("POST", "something.php", true);
xhttp.setRequestHeader("Content-Type", "application/json");
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
// do something
}
};
var data = {some: "thing"};
xhttp.send(JSON.stringify(data));
</code>
then in <code>something.php</code> you can retrieve your json by doing
<?php
$data = json_decode(file_get_contents("php://input"), true);
?>
