Xojo Plugin

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. Xojo Plugin

Dim success As Boolean
success = False

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

Dim zip As New Chilkat.Zip

// Open an unencrypted .zip
success = zip.OpenZip("qa_data/zips/test.zip")
If (success <> True) Then
    System.DebugLog(zip.LastErrorText)
    Return
End If

// Unzip to a temp directory.
Dim numFilesUnzipped As Int32
numFilesUnzipped = zip.Unzip("qa_output/tmp")
If (numFilesUnzipped < 0) Then
    System.DebugLog(zip.LastErrorText)
    Return
End If

// Clear the zip object.
success = zip.NewZip("qa_output/aesTest.zip")

// Indicate that 128-bit AES encryption is to be used when writing the .zip
zip.Encryption = 4
zip.EncryptKeyLength = 128

// Set the password.
zip.EncryptPassword = "secret"

// Append the files.
zip.AppendFromDir = "qa_output/tmp"
success = zip.AppendFiles("*.*",True)
If (success <> True) Then
    System.DebugLog(zip.LastErrorText)
    Return
End If

// Write the .zip and close it.
success = zip.WriteZipAndClose()
If (success <> True) Then
    System.DebugLog(zip.LastErrorText)
    Return
End If

System.DebugLog("Success.")