What’s the Difference Between zip_read and fopen? When Should You Use zip_entry_read Instead of fopen?

In PHP, there are many ways to handle files. fopen is one of the most commonly used functions for opening regular files for reading and writing. When working with files inside a ZIP archive, however, you’ll typically use zip_read and related functions, such as zip_entry_read. This article provides a detailed comparison of these two approaches and explores the scenarios where zip_entry_read should be used instead of fopen.

1. Introduction to fopen

fopen is a fundamental PHP function for file operations. It can open both local files and remote files (for example: http://m66.net/path/to/file) for reading or writing. It's straightforward to use and ideal for handling standard files.

<?php
$handle = fopen("http://m66.net/example.txt", "r");
if ($handle) {
    while (($line = fgets($handle)) !== false) {
        echo $line;
    }
    fclose($handle);
} else {
    echo "Unable to open file";
}
?>

The code above opens a plain text file and reads its contents line by line in a loop.

2. Introduction to zip_read and zip_entry_read

zip_read is part of PHP’s Zip extension and is used to read entries from within a ZIP archive. You use zip_open to open the archive, zip_read to iterate through its entries, and zip_entry_read to extract the contents of individual files.

Example code:

<?php
$zip = zip_open("/path/to/archive.zip");
if ($zip) {
    while ($entry = zip_read($zip)) {
        $name = zip_entry_name($entry);
        echo "Filename: $name\n";
        if (zip_entry_open($zip, $entry, "r")) {
            $content = "";
            while ($data = zip_entry_read($entry, 1024)) {
                $content .= $data;
            }
            echo $content;
            zip_entry_close($entry);
        }
    }
    zip_close($zip);
}
?>

In this example, we open a ZIP archive, loop through all its entries, and read the content of each file.

3. Key Differences

4. When Should You Use zip_entry_read Instead of fopen?

• The file is inside a ZIP archive
  If the file is part of a compressed archive, you can’t directly access it using fopen (even with protocols like zip://, which are only partially supported in some environments). Instead, use zip_open and zip_entry_read to read it.

• You need to handle compressed content
  zip_entry_read automatically decompresses the content for you, eliminating the need for manual extraction. It's more efficient.

• To save disk space or avoid temporary files
  Using zip_entry_read allows you to access files directly within an archive without extracting them first, saving space and avoiding extra steps.

• For chunked reading of large files
  zip_entry_read supports reading data in chunks, making it suitable for processing large files without consuming too much memory.

5. Summary

• fopen is used for opening regular files and supports multiple protocols. It's simple and direct to use.

• zip_read and zip_entry_read are specifically for ZIP archives, enabling easy access to compressed contents.

• If the file resides inside a ZIP archive, you must use zip_entry_read, as fopen cannot access it directly.

• The method you choose depends on your use case. When working with ZIP contents, zip_entry_read is the go-to option.

• Related Tags:

  fopen