Delphi DLL 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.

Delphi DLL

var
success: Boolean;
zip: HCkZip;
charset: PWideChar;
zip2: HCkZip;
entry: HCkZipEntry;

begin
success := False;

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

zip := CkZip_Create();

success := CkZip_NewZip(zip,'original.zip');
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip));
    Exit;
  end;

charset := 'utf-8';

success := CkZip_AddString(zip,'a.txt','Contents of file A',charset);
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip));
    Exit;
  end;

success := CkZip_AddString(zip,'b.txt','Contents of file B',charset);
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip));
    Exit;
  end;

success := CkZip_AddString(zip,'c.txt','Contents of file C',charset);
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip));
    Exit;
  end;

//  Write the ZIP archive to disk.
//  
//  The ZIP now contains:
//  
//      a.txt
//      b.txt
//      c.txt
//  
success := CkZip_WriteZipAndClose(zip);
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip));
    Exit;
  end;

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

zip2 := CkZip_Create();

success := CkZip_OpenZip(zip2,'original.zip');
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip2));
    Exit;
  end;

//  Find the entry named "b.txt".
entry := CkZipEntry_Create();

success := CkZip_EntryOf(zip2,'b.txt',entry);
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip2));
    Exit;
  end;

//  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 := CkZip_DeleteEntry(zip2,entry);
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip2));
    Exit;
  end;

//  Write the modified ZIP archive to a new file.
CkZip_putFileName(zip2,'modified.zip');

success := CkZip_WriteZipAndClose(zip2);
if (success = False) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip2));
    Exit;
  end;

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

Memo1.Lines.Add('ZIP archive updated successfully.');

CkZip_Dispose(zip);
CkZip_Dispose(zip2);
CkZipEntry_Dispose(entry);