(VB.NET) Open a Zip Archive

See more Zip Examples

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

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Dim zip As New Chilkat.Zip

' Open a non-encrypted .zip
Dim success As Boolean = zip.OpenZip("qa_data/zips/sample.zip")
If (success <> True) Then
    Debug.WriteLine(zip.LastErrorText)
    Exit Sub
End If

Debug.WriteLine("Num entries = " & 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) Then
    Debug.WriteLine(zip.LastErrorText)
    Exit Sub
End If

Debug.WriteLine("Num entries = " & zip.NumEntries)

' ...
' ...

zip.CloseZip()