Append Files to Existing Zip w/out Rewriting Entire Zip

Demonstrates how to use the QuickAppend method to append files to an existing .zip archive. This method works by editing the existing .zip -- it does not rewrite or recompress the contents of the existing .zip. It is the fastest way to append additional files to a pre-existing large .zip archive. Note: The QuickAppend method is new and available in the pre-release downloads, or in official releases dated after 6-October-2007.

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

bool success;

//  Any string unlocks the component for the 1st 30-days.
success = zip.UnlockComponent("Anything for 30-day trial");
if (success != true) {
    MessageBox.Show(zip.LastErrorText);
    return;
}

//  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) {
    MessageBox.Show(zip.LastErrorText);
    return;
}

//  Add a reference to a file.  This is the file that will
//  be added to a pre-existing .zip archive.
//  Note: this does not read or compress the file contents --
//  it simply adds a reference to the zip object.
bool saveExtraPath;
saveExtraPath = false;
success = zip.AppendOneFileOrDir("something.dat",saveExtraPath);
if (success != true) {
    MessageBox.Show(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 = zip.QuickAppend("preExisting.zip");
if (success != true) {
    MessageBox.Show(zip.LastErrorText);
    return;
}

MessageBox.Show("Success!");

//  Note: Additional files, directory trees, or in-memory data
//  can be appended by calling AppendOneFileOrDir, AppendFiles,
//  AppendString, AppendData, etc. multiple times.
//  Whatever files and/or in-memory data that are referenced by
//  this zip object will be appended to preExisting.zip when
//  QuickAppend is called.