How to download a file and modify its name using PHP

PHP is a popular server-side scripting language used for developing dynamic web applications. In PHP, file downloading is a common operation. Sometimes, the name of the file we need to download may be different from the actual file name. In this article, we will explain how to download a file and change its name using PHP.

1. Download the file

In PHP, you can use the readfile() function to read the file and send it to the browser. The following is an example of a basic download.php file that will download the specified file.

$file = $_GET['file'];

if (file_exists($file)) {
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename="' . basename($file) . '"');
    header('Content-Length: ' . filesize($file));
    readfile($file);
    exit;
}

In the above code, we first get the file name to be downloaded. Then we check if the file exists. If the file exists, we set the HTTP headers for the file type, file name, and file size, send the file to the browser using the readfile() function, and finally exit the script.

2. Modify the file name

If we need to modify the name of the downloaded file, we can modify the file name in the above code. For example, we can modify the above code to the following, where the new file name is prefixed with "downloaded_":

$file = $_GET['file'];
$newFileName = "downloaded_" . basename($file);

if (file_exists($file)) {
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename="' . $newFileName . '"');
    header('Content-Length: ' . filesize($file));
    readfile($file);
    exit;
}

In the above code, we have added a new variable $newFileName, the new name used to store the downloaded file. In the header() function, we replaced basename($file) with the new filename. This will set the downloaded file name to the new name.

3. Other modification methods

In addition to directly modifying the file name in the header() function, we can also use other methods to modify the file name. For example, we can use the rename() function in PHP to rename files.

The following is a sample code that changes the name of the downloaded file to "downloaded_" filename:

$file = $_GET['file'];
$newFileName = "downloaded_" . basename($file);

if (file_exists($file)) {
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename="' . $newFileName . '"');
    header('Content-Length: ' . filesize($file));

    rename($file, $newFileName);

    readfile($newFileName);
    exit;
}

In the above code, we added a rename() Function renames the downloaded file to a new file name. We then use the readfile() function to send the new file to the browser, and finally exit the script.

Summary:

Downloading files and modifying file names in PHP is a common requirement. We can use the readfile() function to read the file and send it to the browser, and we can also use the header() function to set the HTTP file type, file name and file size Header. If we need to modify the file name, we can modify it directly in the header() function, or use the rename() function in PHP to rename the file.

The above is the detailed content of How to download a file and modify its name using PHP. For more information, please follow other related articles on the PHP Chinese website!