PHP JSON

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

Environment configuration

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

JSON Function

Function                                                                              ##json_encode JSON encoding of variables
json_decode Decodes strings in JSON format and converts them into PHP variables

json_last_error Returns the last error that occurred

JSON specifications

1) Parallel data are separated by commas (", ").

2) Mapping is represented by colon (": ").

3) The collection (array) of parallel data is represented by square brackets ("[]").

4) The mapped collection (object) is represented by curly brackets ("{}").

##json_encode

##PHP json_encode() is used to JSON encode variables. This function returns JSON data if executed successfully, otherwise it returns FALSE. Syntax
string json_encode ( $value [, $options = 0 ] )

Parameters

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

2. options: Binary mask composed 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_OBJECTExample

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

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

The execution result of 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 above code execution The result is:

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

##json_decode

PHP json_decode() function Used to decode JSON formatted strings and convert them into PHP variables.
Syntax

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

Parameters

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

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

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

4. options: Binary mask, currently only supports JSON_BIGINT_AS_STRING.

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 execution result of 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)
}