PHPJSON

In this chapter we will introduce how to use PHP language to encode and decode JSON objects.

Environment configuration

JSON extension has been built-in in php5.2.0 and above.

JSON functions

json_encode

PHP json_encode() is used to JSON encode variables. This function returns JSON data if executed successfully, otherwise it returns FALSE.

grammar

 string json_encode ( $value [, $options = 0 ] )

parameter

value : The value to encode. This function is only valid for UTF-8 encoded data.

options : Binary mask consisting of the following constants: JSON_HEX_QUOT, JSON_HEX_TAG, JSON_HEX_AMP, JSON_HEX_APOS, JSON_NUMERIC_CHECK, JSON_PRETTY_PRINT, JSON_UNESCAPED_SLASHES, JSON_FORCE_OBJECT

Example

The following example demonstrates how to convert a PHP array to JSON format data:

 <?php $arr = array('a' => 1, 'b' => 2, 'c' => 3, 'd' => 4, 'e' => 5); echo json_encode($arr) ;?>

The result of executing the above code is:

 {"a":1,"b":2,"c":3,"d":4,"e":5}

The following example demonstrates how to convert PHP objects into JSON format data:

 <?php class Emp { public $name = ""; public $hobbies = ""; public $birthdate = ""; } $e = new Emp(); $e->name = "sachin"; $e-> hobbies = "sports"; $e->birthdate = date('m/d/Y h:i:s a', "8/5/1974 12:20:03 p"); $e->birthdate = date('m/d/Y h:i:s a', strtotime("8/5/1974 12:20:03")); echo json_encode($e);?>

The result of executing the above code is:

 {"name":"sachin","hobbies":"sports","birthdate":"08/05/1974 12:20:03 pm"}

json_decode

The PHP json_decode() function is used to decode JSON-formatted strings and convert them into PHP variables.

grammar

 mixed json_decode ($json_string [,$assoc = false [, $depth = 512 [, $options = 0 ]]])

parameter

json_string : JSON string to be decoded, must be UTF-8 encoded data

assoc : When this parameter is TRUE, an array will be returned, and when FALSE, an object will be returned.

depth : parameter of integer type, which specifies the recursion depth

options : Binary mask, currently only JSON_BIGINT_AS_STRING is supported.

Example

The following example demonstrates how to decode JSON data:

 <?php $json = '{"a":1,"b":2,"c":3,"d":4,"e":5}'; var_dump(json_decode($json)); var_dump (json_decode($json, true));?>

The result of executing the above code is:

 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)}