php - Empty json_encode -

below php code. makes query on database, puts data array , , try pass json , print these same data.

the problem print coming out empty. using print_r can print data array, when pass data json , return null. how can fix this?

<?php             $user = "root";     $password = "";     $db = "angulardb";     $host = "localhost";     $con = mysqli_connect("localhost", $user, $password, $db);      if (mysqli_connect_errno()){       echo "failed connect mysql: " . mysqli_connect_error();     }      $usuario = mysqli_query($con, "select *  users");      if (!$usuario) {         echo "não foi possível executar consulta no banco de dados: " . mysql_error();         exit;      }      $return = array();      while ($dados = mysqli_fetch_assoc($usuario)) {         $return[] = $dados;      }     header('content-type: application/json');        echo json_encode($return);  ?> 

database:

create table if not exists `users` (   `id` int(6) not null auto_increment,   `nome` varchar(50) not null,   `email` varchar(50) not null,   `pass` varchar(50) not null,   primary key (`id`) ) engine=innodb  default charset=latin1 auto_increment=4 ;  insert `users` (`id`, `nome`, `email`, `pass`) values (2, 'joão silva', 'joao.silva@angular.com', '123456'), (3, 'mario de almeida', 'mario.almeida@angular.com', '123456'); 

this due fact, data returned database might contain non-utf-8 character.

you can try :

json_encode($data, json_unescaped_unicode) 

or

json_decode($json, false, 512, json_unescaped_unicode) 

also try out answer in link : how json_encode() work iso-8859-1 (åäö)