AngularJs - $http.Get不起作用

无法从PHP文件中获取数据。

require 'dbconnect.php';
$array_data = array();
$query = "SELECT * FROM user";
$stmt = $conn->prepare($query);
$stmt->execute($array_data);
$result_data = $stmt->fetchAll( PDO::FETCH_ASSOC );
if( !empty($result_data) ) {    
    header('Content-type: application/json');
    $json = json_encode($result_data);
    // echo $json;
    echo preg_replace("/null/", '""', $json); // replace null to ""
}

controller.js

.controller('tableCtrl', function($filter, $sce, ngTableParams, tableService) {
        var data = tableService.data
    //Editable
        this.tableEdit = new ngTableParams({
            page: 1,            // show first page
            count: 10           // count per page
        }, {
            total:data.length, // length of data
            getData: function($defer, params) {
                $defer.resolve(data.slice((params.page() - 1) * params.count(), params.page() * params.count()));
            }
        });
    })

script.js

.service('tableService', ['$http', function($http){
        this.data = $http.get("data/timesheet.json")
    }])

<table ng-table="tctrl.tableEdit" class="table table-striped table-vmiddle">
       <tr ng-repeat="w in $data"  ng-class="{ 'active': w.$edit }">
          <td data-title="'ID'">
             <span ng-if="!w.$edit">{{ w.id }}</span>
             <div ng-if="w.$edit"><input class="form-control" type="text" ng-model="w.id" /></div>
          </td>
          ...
       </tr>                        
   </table> 

当我像这样把json数据放到service.js中时。数据= [{..}]它的工作，但现在我只是试图从php文件，这是不工作和得到空白表拉数据。谁能告诉我这里少了什么吗?我对AngularJS很陌生