B4X Requires Chilkat v11.0.0+

Remove an Entry from an Existing ZIP Using DeleteEntry

See more Zip Examples

This example demonstrates how to use the DeleteEntry method to remove a file from an existing ZIP archive.

The example:

• Creates a ZIP archive containing three text files
• Opens the ZIP archive for modification
• Finds and deletes one entry
• Writes the modified ZIP archive to a new filename

Suppose the original ZIP archive contains:

a.txt
b.txt
c.txt

After deleting b.txt, the modified ZIP archive contains:

a.txt
c.txt

The entry is removed only from the in-memory ZIP object until a Write* method is called.

B4X

Dim success As Boolean = False

'  ------------------------------------------------------------
'  First create a ZIP archive containing three text files.

Dim zip As ChilkatZip
zip.Initialize("zip")

success = zip.NewZip("original.zip")
If success = False Then
    Log(zip.LastErrorText)
    Return
End If


Dim charset As String = "utf-8"

success = zip.AddString("a.txt", "Contents of file A", charset)
If success = False Then
    Log(zip.LastErrorText)
    Return
End If


success = zip.AddString("b.txt", "Contents of file B", charset)
If success = False Then
    Log(zip.LastErrorText)
    Return
End If


success = zip.AddString("c.txt", "Contents of file C", charset)
If success = False Then
    Log(zip.LastErrorText)
    Return
End If


'  Write the ZIP archive to disk.
'  
'  The ZIP now contains:
'  
'      a.txt
'      b.txt
'      c.txt
'  
success = zip.WriteZipAndClose
If success = False Then
    Log(zip.LastErrorText)
    Return
End If


'  ------------------------------------------------------------
'  Open the existing ZIP archive for modification.

Dim zip2 As ChilkatZip
zip2.Initialize("zip2")

success = zip2.OpenZip("original.zip")
If success = False Then
    Log(zip2.LastErrorText)
    Return
End If


'  Find the entry named "b.txt".
Dim entry As ChilkatZipEntry
entry.Initialize("entry")

success = zip2.EntryOf("b.txt", entry)
If success = False Then
    Log(zip2.LastErrorText)
    Return
End If


'  Remove the entry from the in-memory ZIP object.
'  
'  At this point, the original ZIP file on disk is unchanged.
'  The deletion takes effect only after WriteZip or
'  WriteZipAndClose is called.
success = zip2.DeleteEntry(entry)
If success = False Then
    Log(zip2.LastErrorText)
    Return
End If


'  Write the modified ZIP archive to a new file.
zip2.FileName = "modified.zip"

success = zip2.WriteZipAndClose
If success = False Then
    Log(zip2.LastErrorText)
    Return
End If


'  The modified ZIP now contains:
'  
'      a.txt
'      c.txt
'  

Log("ZIP archive updated successfully.")