How to accept an empty input value in CI?

Hi all, I want my app to accept an empty value in the input file uploader How?

PHP Code:

<?= form_open_multipart('upload/upload') ?>

<input type="file" name="userfile" size="20" />/*I want to accept if user did not pick up an image*/


<input type="submit" value="upload" />

</form> 


PHP Code:

$file = $this->request->getFile('userfile');*I want to accept if user did not pick up an image*/

  if ($file->isValid() && ! $file->hasMoved()) {

   $newName = $file->getRandomName();/*Here it generate an error that Undefined variable $newName  but if there is file ok */
  $file->move(WRITEPATH . 'uploads', $newName);
}

'savein'=>$newName,/*Modal*/ 


Codeigniter First, Codeigniter Then You!!

yekrinaDigitals

Could you check empty() on the POST var?

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what about an isset() check? 

PHP Code:

$file = $this->request->getFile('userfile');

if(isset($file)){..things go on..}