How do I rename a filename to a random filename in PHP?

Question

I have a .php file with a random name. And I want to rename it to something another random name when a specific button was hit.

function generateRandomString($length = 10) {
    $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $charactersLength = strlen($characters);
    $randomString = '';
    for ($i = 0; $i < $length; $i++) {
        $randomString .= $characters[rand(0, $charactersLength - 1)];
    }
    return $randomString;

}

if (isset($_SESSION['submit'])) {
    rename(, generateRandomString())
}

I have this code here and I think that I did everything right, but I don't know how to do the rename function

Answer 1

There is a rename function that does exactly what you want. Also you can use uniqid for generating unique names for your files.

Answer 2

you need to look up the rename() function in the PHP docs: http://php.net/manual/en/function.rename.php

if (isset($_SESSION['submit'])) {

    $oldFileName = 'foo.txt';
    $newFileName = generateRandomString() . '.txt';

    rename($oldFileName, $newFileName);

}

This is it in its basic form, but in production you would want to handle errors and store the new filename etc.

Answer 3

To improve the function .

This shuffles an array with the letters/numbers and take the ten first characters.

This should be more efficient than looping.

$characters = array ('0','1','2','3','4','5','6','7','8','9',
'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z',
'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
);
shuffle($characters);
return implode("", array_slice($characters, 0,10));

https://3v4l.org/7dUiN