Merge Zip Archives - Append .zip onto another .zip

Demonstrates how to use the QuickAppend method to append the contents of one .zip archive to another .zip archive. This method works by editing the target .zip -- it does not rewrite the target .zip. It does not recompress (or re-encrypt) the data in either archive. It is the fastest way to append additional files or data 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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Dim zip As New Chilkat.Zip()

Dim success As Boolean

'  Any string unlocks the component for the 1st 30-days.
success = zip.UnlockComponent("Anything for 30-day trial")
If (success <> true) Then
    MsgBox(zip.LastErrorText)
    Exit Sub
End If


'  Open the .zip archive that is to be appended to target.zip.
'  You should open the smaller of the two .zip archives here --
'  to minimize the amount of data to be copied.  When the .zips
'  are merged, nothing is recompressed.  The compressed (and
'  possibly encrypted) data is simply appended to the end
'  of the target .zip.
success = zip.OpenZip("zipToBeAppended.zip")
If (success <> true) Then
    MsgBox(zip.LastErrorText)
    Exit Sub
End If


'  Appends the contents of this zip object to the target.zip
'  archive.  After calling QuickAppend, target.zip will contain
'  both its original contents as well as the contents of
'  "zipToBeAppended.zip".
success = zip.QuickAppend("target.zip")
If (success <> true) Then
    MsgBox(zip.LastErrorText)
    Exit Sub
End If


MsgBox("Success!")