How to rename uploaded file before saving it into a directory?

Question

Below is the code I used in order to upload files into a directory. It works fine. My main question is:

move_uploaded_file() is the one that saves the uploaded file into the directory, and it is also my guess that move_uploaded_file() is the one that sets the name for it.

How could I change the name of my file to a random number?

I have tried to do so below:

$allowedExts = array("gif", "jpeg", "jpg", "png");
$temp = explode(".", $_FILES["file"]["name"]);
$extension = end($temp);
if ((($_FILES["file"]["type"] == "image/gif") || ($_FILES["file"]["type"] == "image/jpeg") || ($_FILES["file"]["type"] == "image/jpg") || ($_FILES["file"]["type"] == "image/pjpeg") || ($_FILES["file"]["type"] == "image/x-png") || ($_FILES["file"]["type"] == "image/png")) && ($_FILES["file"]["size"] < 100000) && in_array($extension, $allowedExts)) {
    if ($_FILES["file"]["error"] > 0) {
        echo "Return Code: " . $_FILES["file"]["error"] . "<br>";
    } else {

        $fileName = $temp[0] . "." . $temp[1];
        $temp[0] = rand(0, 3000); //Set to random number
        $fileName;

        if (file_exists("../img/imageDirectory/" . $_FILES["file"]["name"])) {
            echo $_FILES["file"]["name"] . " already exists. ";
        } else {
            move_uploaded_file($_FILES["file"]["tmp_name"], "../img/imageDirectory/" . $_FILES["file"]["name"]);
            echo "Stored in: " . "../img/imageDirectory/" . $_FILES["file"]["name"];
        }
    }
} else {
    echo "Invalid file";
}

I tried changing variables such as the $_FILES["file"]["name"] and replacing it with the $fileName; variable so that the new name can be stored.

Answer 1

You can simply change the name of the file by changing the name of the file in the second parameter of move_uploaded_file.

Instead of

move_uploaded_file($_FILES["file"]["tmp_name"], "../img/imageDirectory/" . $_FILES["file"]["name"]);

Use

$temp = explode(".", $_FILES["file"]["name"]);
$newfilename = round(microtime(true)) . '.' . end($temp);
move_uploaded_file($_FILES["file"]["tmp_name"], "../img/imageDirectory/" . $newfilename);

Changed to reflect your question, will product a random number based on the current time and append the extension from the originally uploaded file.