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PHP Extension

Encrypt Already Existing Zip

See more Zip Examples

To encrypt an already existing non-encrypted .zip, the application must open the .zip, set the encryption related properties, and then re-write.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

// This requires the Chilkat Zip API to have been previously unlocked.
// See Unlock Chilkat Zip for sample code.

$zip = new CkZip();

// Open an unencrypted .zip
$success = $zip->OpenZip('qa_data/zips/test.zip');
if ($success != true) {
    print $zip->lastErrorText() . "\n";
    exit;
}

// Unzip to a temp directory.
$numFilesUnzipped = $zip->Unzip('qa_output/tmp');
if ($numFilesUnzipped < 0) {
    print $zip->lastErrorText() . "\n";
    exit;
}

// Clear the zip object.
$zip->NewZip('qa_output/aesTest.zip');

// Indicate that 128-bit AES encryption is to be used when writing the .zip
$zip->put_Encryption(4);
$zip->put_EncryptKeyLength(128);

// Set the password.
$zip->put_EncryptPassword('secret');

// Append the files.
$zip->put_AppendFromDir('qa_output/tmp');
$success = $zip->AppendFiles('*.*',true);
if ($success != true) {
    print $zip->lastErrorText() . "\n";
    exit;
}

// Write the .zip and close it.
$success = $zip->WriteZipAndClose();
if ($success != true) {
    print $zip->lastErrorText() . "\n";
    exit;
}

print 'Success.' . "\n";

?>