(C#) Open a Zip Archive

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Demonstrates how to open a zip, or an encrypted .zip, or a legacy password-protected .zip.

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Chilkat.Zip zip = new Chilkat.Zip();

// Open a non-encrypted .zip
bool success = zip.OpenZip("qa_data/zips/sample.zip");
if (success != true) {
    Debug.WriteLine(zip.LastErrorText);
    return;
}

Debug.WriteLine("Num entries = " + Convert.ToString(zip.NumEntries));

// ...
// ...

zip.CloseZip();

// ----------------------------------------------------------------------------
// Open an encrypted zip...

// The two main types of encryption used in ZIP archives are Password-Protected and AES.
// 

// ---------------------------------------
// 1. Legacy Password-Protected Zip
// 
// This is the older and less secure method of encrypting ZIP archives. 
// It provides a basic level of security, but is considered weak by modern standards. 
// It is vulnerable to various attacks, including known-plaintext attacks and brute force attacks.
// Although Chilkat allows it, you shouldn't create new zip archives using legacy password-protection.

// ---------------------------------------
// 2. AES Encrypted Zip
// 
// AES encryption is a more modern and secure method for encrypting ZIP archives. 
// It provides strong encryption based on the AES algorithm, which is widely regarded as secure. 
// AES supports different key lengths, typically 128-bit, 192-bit, and 256-bit.

// When opening an encrypted zip, your application only needs to provide the correct password.
// The information about the type of encryption and the key length (if AES) is already embedded within the encrypted .zip.

// Provide the decrypt password because we are opening an existing .zip (decrypting)
zip.DecryptPassword = "thePassword";

success = zip.OpenZip("qa_data/zips/encryptedSamples/ziptest_256.zip");
if (success != true) {
    Debug.WriteLine(zip.LastErrorText);
    return;
}

Debug.WriteLine("Num entries = " + Convert.ToString(zip.NumEntries));

// ...
// ...

zip.CloseZip();