function exibirAulas() {

	var pesquisa = $('#pesquisa').val();

	$.ajax({
		url:'http://localhost/estoque/usuario/pegar_aulas',
		type:'POST',
		data:{pesquisa:pesquisa},
		dataType:'json',
		success:function(json) {
			var html = '';


				if(isEmpty(json)) {
					$("#dataUsuario").html('Dados não encontrados!');
					return false;
				}

				for(var i in json) {

		                if(json.status != 1) {
		      		        html += '<tr class="table-danger">';
		                } else {
		                  	html += '<tr>';
		                }

							html +='<td>'+json.email+'</td>'+

							'<td>'+'<img class="img img-thumbnail rounded imguserlist"'+ 'src=../assets/images/'+json.foto+'></img> </td>'+

							'<td>'+json.status+'</td>'+
							'<td>'+json.datainclusao+'</td>'+
							'<td class="text-center">'+
	                  			'<a class="btn btn-outline-primary" href="editar/'+json.id+'">Editar</a>'+
	                  			'<a class="btn btn-outline-danger" href="excluir/'+json.id+'">Excluir</a>'+
	                  			'<a class="btn btn-outline-success" href="listar/'+json.id+'">Visualizar</a>'+
	              			 '</td>'+
						'</tr>'
				}

			   $("#dataUsuario").html('<table class="table table-bordered table-hover text-center">'+
			        '<thead class="thead-inverse text-center">'+
			                '<tr>'+
			                    '<th class="text-center">E-mail</th>'+
			                    '<th class="text-center">Foto</th>'+
			                    '<th class="text-center">Status</th>'+
			                    '<th class="text-center">Data Inclusão</th>'+
			                    '<th class="text-center">Ações</th>'+
			                '</tr>'+
			        '</thead>'+
			 '</tbody>'+
		'</table>'+html);


		}
	});
}


	public function pegar_aulas() {

   		$usuario = new Usuario();

    	if(isset($_POST['pesquisa']) && !empty($_POST['pesquisa'])) {

    		$value = $_POST['pesquisa'];

       		$usuario->listUsuarioAjax($value);

    		$array = $usuario->listUsuarioAjax($value);

			echo json_encode($array);

    		exit;

    		} else {
    			$array = $usuario->listUsuarioAjax("");
    			print_r($array);
				echo json_encode($array);
    			exit;
    		}

    }

Resposta navegador:

{0: "344", 1: "rodrigues.caio1985@gmail.com", 2: "7363a0d0604902af7b70b271a0b96480",…}
0
:
"344"
1
:
"rodrigues.caio1985@gmail.com"
2
:
"7363a0d0604902af7b70b271a0b96480"
3
:
"b9b9503dd602b6ebe44aa1d2fbf530b5"
4
:
"2"
5
:
"2018-01-26 18:25:27"
6
:
"2018-01-27 17:53:54"
7
:
"1"
8
:
"1516998472.jpg"
dataalteracao
:
"2018-01-27 17:53:54"
datainclusao
:
"2018-01-26 18:25:27"
email
:
"rodrigues.caio1985@gmail.com"
foto
:
"1516998472.jpg"
id
:
"344"
idpessoa
:
"1"
senha
:
"7363a0d0604902af7b70b271a0b96480"
status
:
"2"
token
:
"b9b9503dd602b6ebe44aa1d2fbf530b5"


Response:

{"id":"344","0":"344","email":"rodrigues.caio1985@gmail.com","1":"rodrigues.caio1985@gmail.com","senha":"7363a0d0604902af7b70b271a0b96480","2":"7363a0d0604902af7b70b271a0b96480","token":"b9b9503dd602b6ebe44aa1d2fbf530b5","3":"b9b9503dd602b6ebe44aa1d2fbf530b5","status":"2","4":"2","datainclusao":"2018-01-26 18:25:27","5":"2018-01-26 18:25:27","dataalteracao":"2018-01-27 17:53:54","6":"2018-01-27 17:53:54","idpessoa":"1","7":"1","foto":"1516998472.jpg","8":"1516998472.jpg"}