Codeigniter Image Uploading无法在线工作

我有一个neede照片上传的应用程序，已经在codeigniter中完成，在localhost上正常工作，但它不能在线工作 .

VIEW PAGE CODE :

<div> 
                  <form id="uploadimage" method="POST" name="uploadimage" action="<?php echo base_url(); ?>onebachhpan/savephoto" enctype="multipart/form-data">
                    <input type="file" name="userfile" id="userfile" accept="image/*" />


                    <input type="submit" class="button_example" id="upload_button" name="upload_button" value="Upload"/>
             </form>
             

             <form  id="removeimage" method="POST" name="removeimage" action="<?php echo base_url(); ?>onebachhpan/removephoto" enctype="multipart/form-data">
                   <input type="submit" style="position: absolute; left: 100px; top: 64px; " class="button_example" id="delete_button" name="delete_button" value="Delete"/>
             </form>
             </div>

以下是图像上传的控制器代码：这在localhost上工作正常：

CONTROLLER CODE:

function savephoto()
    {
         $this->load->library('session');
        $this->load->library('image_lib');
        $config['image_library'] = 'gd2';
        $config['upload_path'] = './profilepic/'; //location to store image
        $config['allowed_types'] = 'gif|jpg|png';
        $this->load->library('upload', $config);
        if ( ! $this->upload->do_upload('userfile'))
        {
            $error = array('error' => $this->upload->display_errors());
         redirect(base_url().'uploaderror');


        }
        else
        {
            $photo = $this->upload->data();
            $data['photo'] = $photo;    
            $id = $this->session->userdata('MemberId');
            $filename = $photo['file_name'];
            $extension = $photo['file_ext'];

            $this->load->model('profile_model');
            $this->profile_model->photo($extension,$id);



          // echo "<pre>";print_r($photo);
            $newpath = './profilepic/'.$id.$extension;

            $config['source_image'] = './profilepic/'.$filename;
            $config['overwrite']=true;

            $config['new_image'] = $newpath;

            $config['width']  = '170';
            $config['height']  = '240';
            $config['maintain_ratio'] = true;


            //$this->load->library('image_lib', $config);

            $this->image_lib->initialize($config);
            $this->image_lib->resize();
            unlink('./profilepic/'.$filename);
            //$this->load->view('onebachhpan_index');
            redirect(base_url().'profile');

        }   
    }