问题是当上传图像时，每次都显示相同的错误“上传路径似乎无效”。尝试了这么多的解决方案，但仍然有相同的问题。请帮助。
控制器：

public function updateprofile()
        {
            /***get current user data***/
            $this->load->model('Admin_main','userinfo');
            $data=$this->userinfo->getuserdata();
            $this->load->model('Admin_main','updateprofile');
            $result=$this->updateprofile->updatemyprofile();
            if($data->identity=='admin')
            {
             redirect('admin/myprofile'); 
            }
            else
            {
             redirect('campuser/myprofile');
            }

        }

产品型号：

if($_FILES['fileToUpload']['name']!='')
        {
                 $config["upload_path"] =  './uploads/'; 
                 $config["allowed_types"] = 'jpg|jpeg|png|gif';
                 $config['max_width'] = 0;
                 $config['max_height'] = 0;
                 $config['max_size'] = 0;
                 $config['encrypt_name'] = TRUE;
                //Load upload library and initialize configuration
                 $this->load->library('upload',$config);
                 $this->upload->initialize($config);
                if($this->upload->do_upload('fileToUpload')){
                    $uploadData = $this->upload->data();
                    $picture = $uploadData['file_name'];
                    $mypic = array('profile_pic'=>$picture);
                    $this->db->set($mypic);
                    $this->db->where('id', $userid);
                    $uppic=$this->db->update('mokhayam_users');
                }
                else
                {
                    echo $this->upload->display_errors();
                }
            }

查看方式：

<form class="form-horizontal" action="admin/updateprofile" method="post" enctype="multipart/form-data">
             <div class="form-group">
             <label class="col-sm-2 control-label">Profile Picture</label>
           <div class="col-sm-10">
        <label for="fileToUpload"><img src="assets/admin/dist/img/gul.jpg" id="blah1" class="profile-user-img img-responsive img-circle"/></label><input type="file" name="fileToUpload" id="fileToUpload" onchange="$('#blah1')[0].src = window.URL.createObjectURL(this.files[0])">
                            </div>
                              </div>
            <input type="hidden" name="userid" value="2"> 
                              <div class="form-group">
                                <div class="col-sm-offset-2 col-sm-10">
   <button type="submit" class="btn btn-success">Submit</button>
            </div>
           </div>
</form>

提前感谢。