我可以'；t在codeigniter上将json对象验证为POST

在我的REST应用程序中，我试图将一个json对象发送到我的API服务器，服务器必须验证数据以确保每件事都按预期进行。

在API服务器上进行验证的控制器

$this->load->model('api/central');
$this->load->library('form_validation');
//validation rules
$this->form_validation->set_error_delimiters('', '');
$this->form_validation->set_rules('id', 'id', 'required|numeric');
$this->form_validation->set_rules('manager', 'manager', 'required|numeric');
$this->form_validation->set_rules('department', 'department', 'required');
$this->form_validation->set_rules('level', 'level', 'required|numeric');

if ($this->form_validation->run() === FALSE) {
    $employeeId = $this->form_validation->error('id') ? $this->form_validation->error('id') : $this->post('id');
    $manager = $this->form_validation->error('manager') ? $this->form_validation->error('manager') : $this->post('manager');
    $department = $this->form_validation->error('department') ? $this->form_validation->error('department') : $this->post('department');
    $level = $this->form_validation->error('level') ? $this->form_validation->error('level') : $this->post('level');
    $response = array(
        'status' => FALSE,
        'error' => 'We don''t have data to display, Minimum information required to process the request is missing',                
        'authenticated' => TRUE,                
        'id' => $employeeId,
        'manager' => $manager,
        'department' => $department,
        'level' => $level                
    );
    $this->response($response, 200);
} else {
    $response = $this->central->calls_get($this->post('id'), $this->post('manager'), $this->post('department'), $this->post('level'));
    $this->response($response, 200);
}

$this->post('id'), $this->post('manager'), $this->post('department'), $this->post('level')返回已提交的值，但form_validation库始终无法验证数据，尽管数据按预期发送

以下是一些有用的http信息http头（'content-type'）='application/json'和通过post发送的数据作为json对象，如：｛"id"："1"，"manager"："2"，"department"："sales"，"level"："3"｝