public function update($id)
{
$role = Role::findOrfail($id);
foreach (array_keys(array_except($this->fields, ['role'])) as $field) {
$role->{$field} = Input::get($field);
}
$role->save();
//分配权限
$permission = new Permission();
$permission->updateRelation($role->id);
return redirect()->route('admin.role.index');
}
