Rename file after uploading

Dears,
I have a form created with 5 files upload fields. Would like to set the file name as below:
"Username_"YYYYMMDDHHMMSS_1"
"Username_"YYYYMMDDHHMMSS_2"
"Username_"YYYYMMDDHHMMSS_3"
"Username_"YYYYMMDDHHMMSS_4"
"Username_"YYYYMMDDHHMMSS_5"

I can make the first part highlighted in blue, but the last part I have no idea how to make it....

The code I use as below:

<?php 
$user =& JFactory::getUser();
return $user->get('username')."_".date("YmdHis")."_".$file_name; ?>

Actually I have set those fields id and fields name as file1, file2, file3.....
not sure if can make use of these....

Thanks for your time.

Best Regards
Wing

Hi Wing,

Not tested but this might work

<?php
foreach ( $files as $k => $v ) {
  if ( $v['name'] == $file_name ) {
   $i = $k+1;
   continue;
  }
}
$user = \JFactory::getUser();
return $user->username."_".date("YmdHis")."_".$file_name."_".$i;
?>

Bob

Tried but failed... :-(

I used the file named: abc.jpg
and it will be renamed as something like: admin_20150724085710_abc.jpg_

Btw, your code should be in "file name code" under "File Upload action"@onSubmit, right?

Hi Wing,

I experimented and many uploads later this version appears to work as long as there are no special characters in the file names

<?php
foreach ( $_FILES as $k => $v ) {
  if ( $v['name'] == $file_name ) {
   $i = substr($k, 4, 1);
   continue;
  }
}
$user = \JFactory::getUser();
return $user->username."_".date("YmdHis")."_".$file_name."_".$i;
?>

Bob