是否有更好的多部分/表单数据验证方法

I have a multipart/form-data with an image upload and some personal data, so I want to include file upload in form validation, I can successfully do this.

However, I now find that there is an issue, ie even if my other form fields have errors and upload file field with no error, then image uploads to folder, how to prevent this, I mean, in my case, If name, email, file fields validation is ok then only file should upload, if name filed validation fails and file field validation ok then file should not upload

here is the code I use:

In Controller:

 <?php
    public $_rules = array(
            'name'=>array('field'=>'name', 'label'=>'Name', 'rules'=>'trim|required'),
            'email'=>array('field'=>'email', 'label'=>'Email', 'rules'=>'trim|required|valid_email'),       
            'profile_img'=>array('field'=>'profile_img', 'label'=>'Design', 'rules'=>'callback__profile_upload')
            );

public function profile()
    {       
        $this->load->library('upload');
        $rules = $this->_rules; 
        $this->form_validation->set_rules($rules);

        if($this->form_validation->run()==TRUE){
            die('success');
        }else {         
            $this->data['content'] =  'frontend/pages/place_order';
            $this->load->view('frontend/_layout_main', $this->data);
        }

    }

function _profile_upload(){
  if($_FILES['profile_img']['size'] != 0 && !empty($_FILES['profile_img']) ){
    $upload_dir = './profile_pics/';
    if (!is_dir($upload_dir)) {
         mkdir($upload_dir);
    }   
    $config['upload_path']   = $upload_dir;
    $config['allowed_types'] = 'gif|jpg|png|jpeg';
    $config['file_name']     = 'profile_img_'.substr(md5(rand()),0,7);
    $config['overwrite']     = false;
    $config['max_size']  = '5120';

     $this->upload->initialize($config);
        if (!$this->upload->do_upload('profile_img')){
            $this->form_validation->set_message('_profile_upload', $this->upload->display_errors());
            return false;
        }   
        else{
            $this->upload_data['file'] =  $this->upload->data();
            return true;
        }   
    }   
    else{
        $this->form_validation->set_message('_profile_upload', "No file selected");
        return false;
    }
}

IN VIEW:

<?php echo form_open_multipart();?>
 <?php $name_err = (!empty(form_error('name'))) ? 'err' : ' ';  
     echo form_input('name',set_value('name'), array('placeholder'=>'Name','class'=>" {$name_err } "));
     ?>

 <?php $email_err = (!empty(form_error('email'))) ? 'err' : ' ';  
    echo form_input('email',set_value('email'), array('placeholder'=>'EMail','class'=>" {$email_err } "));
     ?> 
<?php    
echo form_error('profile_img');
echo form_upload(array('name' =>'profile_img', 'class' => 'inputfile inputfile-4', 'id' => 'profile_img'));
?>
     <li><input type="submit" class="special" value="Submit" /></li>

I have got a solution from codexWorld, I have asked same question over there, and they replied with a tutorial, If anybody still looking for a solution here is the link

http://www.codexworld.com/codeigniter-file-upload-validation/

in the validation call back, we just want to do the file type check

public function _profile_upload($str){
        $allowed_mime_type_arr = array('image/jpeg','image/pjpeg','image/png','image/x-png');
        $mime = get_mime_by_extension($_FILES['file']['name']);
        if(isset($_FILES['file']['name']) && $_FILES['file']['name']!=""){
            if(in_array($mime, $allowed_mime_type_arr)){
                return true;
            }else{
                $this->form_validation->set_message('_profile_upload', 'Please select only pdf/gif/jpg/png file.');
                return false;
            }
        }else{
            $this->form_validation->set_message('_profile_upload', 'Please choose a file to upload.');
            return false;
        }
    }

and in the main function we just want to do the same as normal, using do_upload and specifying the upload config items, anyhow there will be a second file type check when the function executes, I think that doesn't matter. The code will look like this::

public function profile()
    {       
        $rules = $this->_rules; 
        $this->form_validation->set_rules($rules);

        if($this->form_validation->run()==TRUE){
             $config['upload_path']   = 'uploads/files/';
            $config['allowed_types'] = 'gif|jpg|png';
            $config['max_size']      = 1024;
            $this->load->library('upload', $config);
            //upload file to directory
            if($this->upload->do_upload('file')){
                $uploadData = $this->upload->data();
                $uploadedFile = $uploadData['file_name'];

                /*
                 *insert file information into the database
                 *.......
                 */

             }else{
                $data['error_msg'] = $this->upload->display_errors();
            }
        }else {         
            $this->data['content'] =  'frontend/pages/place_order';
            $this->load->view('frontend/_layout_main', $this->data);
        }

    }

Try once like this.I think for images not need to set rules like other fields.

public $_rules = array(
        'name'=>array('field'=>'name', 'label'=>'Name', 'rules'=>'trim|required'),
        'email'=>array('field'=>'email', 'label'=>'Email', 'rules'=>'trim|required|valid_email'),       
        );

And

public function profile()
    {       
        $this->load->library('upload');
        $rules = $this->_rules; 
        $this->form_validation->set_rules($rules);

        if($this->form_validation->run()==TRUE){
            die('success');
        }else {    
            if ($this->_profile_upload()) {   //return true if file uploaded successfully otherwise error
                 $this->data['content'] =  'frontend/pages/place_order';
                 $this->load->view('frontend/_layout_main', $this->data);
                }     

        }

    }

yes that is very obvious that your file get uploads even any other fields' validation failed. You have to initiate image uploading only after form validation success. For that simply validate file specific requirement in that callback, and do actual uploads after successful form validation.