Retaining the value in the <input type="file"> field when submit button is clicked

Question

I have got a <input type="file" > field along with other text fields in a form, When i try to upload any files using browse button and then click submit button ,the value in the input type= "file" field disappears , I would like the browsed value to remain in the <input type="file" > field if errors are present in other fields , is there any way i can retain the value that is browsed and for it to remain in the <input type="file" > field when submit button is clicked ,

<form action="form.php" method="post" enctype= multipart/form-data> 

<input type="file" value="$file" name="file"/> 
<input type="text" value="$line" name="line"> 
 <input type="submit"  name="btnsubmit"> 

</form> 

if($_POST['btnsubmit']) 
{
$line =$_POST['line'];
$file =$_FILES['file'] ['name'];

if($line) 
{
//do something
//conditions for   file check   here 

}
else 
//error 

}

Answer 1

It is not possible to do this. Browser security prevents you from pre-populating the File input field, so that websites cannot steal private files of their will without the user authorizing it first (by clicking "Browse..." and choosing a file).

EDIT: It is not possible to do this natively - but you can attempt some CSS wizardry to display the previously chosen file name maybe beside the file input box to hint the user. If you want to try and be really cool, you can also attempt to overlay the browser's native file input text display area with another div that has the previous file name filled in it. But this will prevent clicking on the input area and so is user unfriendly. Too much work, little reward.

Answer 2

This not allowed to be set by any script for security purpose, implemented by browser vendors as file input as readonly.