PHP Delete file - php

Question

I am trying to develop a user page for a forum and I'm kinda struggling with the image upload.
The problem is that I would like to limit the user to only be able to upload one single image, but be able to change it anytime. so basically, I would like to either overwrite the existing file either delete the old picture and add a new one instead.
At this point I have a piece of code that adds a timestamp at the end of the file (which I don't really need actually).
CODE:
if(isset($_POST['upload']))
{
$extension=strstr($_FILES['uploadedfile']['name'], ".");
$filename = "_/userfiles/userpics/".basename($_FILES['uploadedfile']['name'],
$extension);
$target = "_/userfiles/userpics/".basename($_FILES['uploadedfile']['name']);
$valid = true;
if(file_exists($target))
{
$filename = $filename . time();
$target = $filename . $extension;
}
if($valid)
{
// move the file into the folder of our choise
move_uploaded_file($_FILES['uploadedfile']['tmp_name'], $target);
$img_sql = "INSERT INTO sp_userimage (imageid, path, id) value ('', '".$target."', '".$_SESSION['userid']."')";
$img_result = mysql_query($img_sql);
echo "upload sucessfull";
}

Answer 1

Make use of unlink() in PHP Manual.
if(file_exists($target))
{
unlink($target); // deletes file
//$filename = $filename . time();
//$target = $filename . $extension;
}

Answer 2

I think this might be a bit better suited for you. You might have to edit it a tad.
if($valid)
{
// Check if user has a file.
$img_check = mysql_query("SELECT * FROM sp_userimage WHERE id = " . (int) $_SESION['user_id']);
if( mysql_num_rows($img_check) > 0 ){
$row = mysql_fetch_object($img_check);
// Delete the file.
unlink($row->path);
}
// move the file into the folder of our choise
move_uploaded_file($_FILES['uploadedfile']['tmp_name'], $target);
$img_sql = "INSERT INTO sp_userimage (imageid, path, id) value ('', '".$target."', '".$_SESSION['userid']."')";
$img_result = mysql_query($img_sql);
echo "upload sucessfull";
}

Answer 3

It might be easier to normalize the image type (e.g. only jpegs) and then name the file as the userid. For example:
$target = 'userpics' . DIRECTORY_SEPARATOR . $_SESSION['userid'];
move_uploaded_file($_FILES['uploadedfile']['tmp_name'], $target);
This will simply overwrite the old picture with the new one. Given that this type of filename is deterministic, you also don't need to store the filename in the database.

Answer 4

Use unlink() function
read more here PHP unlink
okay ,if u want to delete the file for that particular user only.
then store the filename vs user in some MapTable in db.
mysql_query("CREATE TABLE t_usr_file_map(
usr_id INT NOT NULL ,
file_name VARCHAR(100),
)")
or die(mysql_error());
and at the time of reupload , fetch the filename from the table for that user , unlink it and reupload the fresh one again.
OR,
or u can use PHP file_rename function at the time of upload. rename filename to the userid
rename ( string $oldname , string $newname [, resource $context ] )
and u can always do unlink based on user-id

Answer 5

Its very simple by unlink()
as:
unlink(dirname(__FILE__) . "/../../public_files/" . $filename);

Answer 6

if (file_exists($path))
{
$filename= rand(1,99).$filename;
unlink($oldfile);
}
move_uploaded_file($_FILES['file']['tmp_name'],$filename);