(C# UWP/WinRT) Creates an AES Encrypted Zip with One File Unencrypted

Demonstrates how to create an AES encrypted zip, but also containing one file that is not encrypted. The way we do it is to first create an AES encrypted zip in the usual way, and then we append an unecrypted file to it.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

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

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

bool success = zip.NewZip("qa_output/aes_with_one_unencrypted.zip");
if (success != true) {
    Debug.WriteLine(zip.LastErrorText);
    return;
}

// Set properties to indicate that the Zip should be
// AES encrypted.

// A value of 4 indicates WinZip compatible AES encryption.
zip.Encryption = 4;

// Key length can be 128, 192, or 256 bits.
zip.EncryptKeyLength = 128;

// Set the password for AES encryption:
zip.EncryptPassword = "myPassword";

// Exclude the file helloWorld.txt
// This file will be added unencrypted to the .zip
Chilkat.StringArray saExclusions = new Chilkat.StringArray();
saExclusions.Append("helloWorld.txt");
zip.SetExclusions(saExclusions);

zip.VerboseLogging = true;

// Add a directory tree to be zipped.
bool recurse = true;
// Append from a directory relative to our current working directory.
zip.AppendFromDir = "qa_data/filesToZip";
success = await zip.AppendFilesAsync("*",recurse);
if (success != true) {
    Debug.WriteLine(zip.LastErrorText);
    return;
}

Debug.WriteLine(zip.LastErrorText);

// Writes qa_output/aes_with_one_unencrypted.zip
success = await zip.WriteZipAndCloseAsync();
if (success != true) {
    Debug.WriteLine(zip.LastErrorText);
    return;
}

// ----------------------------------------------
// At this point, we have an encrypted .zip with all 
// files except for helloWorld.txt.
// We'll add helloWorld.txt (unencrypted) to the .zip we just created.

// The NewZip method only initializes the Zip object -- it does
// not create or write a .zip file.

success = zip.NewZip("notUsed.zip");
if (success != true) {
    Debug.WriteLine(zip.LastErrorText);
    return;
}

saExclusions.Clear();
zip.SetExclusions(saExclusions);

// No encryption.
zip.Encryption = 0;

zip.AppendFromDir = "qa_data/filesToZip";

// Add a reference to a file.  This is the file that will
// be added to a already-existing .zip.  
bool saveExtraPath = false;
success = await zip.AppendOneFileOrDirAsync("helloWorld.txt",saveExtraPath);
if (success != true) {
    Debug.WriteLine(zip.LastErrorText);
    return;
}

// Appends the contents of the zip object to the preExisting.zip
// zip archive.  preExisting.zip is opened, and the files
// referenced by this zip object are streamed in, compressed,
// and appended to the end of the archive.
success = await zip.QuickAppendAsync("qa_output/aes_with_one_unencrypted.zip");
if (success != true) {
    Debug.WriteLine(zip.LastErrorText);
    return;
}

Debug.WriteLine("Success!");