Solution to generate nested JSON in PHP_PHP tutorial

PHP generates nested JSON

　({

　"aa": [

　{

　"Id": "0",

　"title": "title",

　},

　{

　"Id": "1",

　"title": "title",

　}

　],

　"bb":[

　{

…

　},

　{

　....

　}

　]

　})

How does PHP generate this nested JSON

　------Solution--------------------

　/**Json data formatting

　* @param Mixed $data data

* @param String $indent indent character, default 4 spaces

* @return JSON

*/

Function jsonFormat($data, $indent=null){

// Recursively perform urlencode operation on each element in the array to protect Chinese characters

array_walk_recursive($data, 'jsonFormatProtect');

// json encode

$data = json_encode($data);

// urldecode the urlencode content

　$data = urldecode($data);

// Indentation processing

$ret = '';

　$pos = 0;

　$length = strlen($data);

　$indent = isset($indent)? $indent : ' ';

　$newline = "n";

$prevchar = '';

$outofquotes = true;

　for($i=0; $i<=$length; $i++){

　$char = substr($data, $i, 1);

　if($char=='"' && $prevchar!='\'){

$outofquotes = !$outofquotes;

　}elseif(($char=='}' ------Solution-------------------- $char==']') && $outofquotes){

　$ret .= $newline;

　$pos --;

　for($j=0; $j<$pos; $j++){

　$ret .= $indent;

　}

　}

　$ret .= $char;

　if(($char==',' ------Solution-------------------- $char=='{' -- ----Solution-------------------- $char=='[') && $outofquotes){

　$ret .= $newline;

　if($char=='{' ------Solution-------------------- $char=='['){

　$pos++;

　}

　for($j=0; $j<$pos; $j++){

　$ret .= $indent;

　}

　}

$prevchar = $char;

　}

return $ret;

　}

　/**Urlencode array elements

* @param String $val

*/

Function jsonFormatProtect(&$val){

　if($val!==true && $val!==false && $val!==null){

　$val = urlencode($val);

　}

　}

Header('content-type:application/json;charset=utf8');

　$arr = array(

　'aa' => array(

array(

　'Id' => 0,

　'title' => 'Title'

　), array( 'Id' => 1, 'title' => 'title' ), ), 'bb' => array( array( 'Id' => 2, 'title' = > 'Title' ), array( 'Id' => 3, 'title' => 'Title' ), ));echo jsonFormat($arr);{ "aa":[ { "Id":" 0", "title":"title" }, { "Id":"1", "title":"title" } ], "bb":[ { "Id":"2", "title":" Title" }, { "Id":"3", "title":"title" } ]}