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Delphi DLL

Replace/Update a FIle in a .zip

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Demonstrates how to replace/update a file from a .zip. Note: This requires the entire .zip to be rewritten.

Chilkat Delphi DLL Downloads

Delphi DLL
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, ZipEntry, Zip;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
zip: HCkZip;
charset: PWideChar;
zip2: HCkZip;
entry: HCkZipEntry;

begin
success := False;

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

// First prepare a .zip and write it..
zip := CkZip_Create();

CkZip_NewZip(zip,'qa_output/abc.zip');

// Add some files..
charset := 'utf-8';
CkZip_AddString(zip,'a.txt','aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa',charset);
CkZip_AddString(zip,'b.txt','bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb',charset);
CkZip_AddString(zip,'c.txt','cccccccccccccccccccccccccccccccccccc',charset);

// Write to qa_output/abc.zip
// This .zip contains three files: a.txt, b.txt, and c.txt
success := CkZip_WriteZipAndClose(zip);

// -------------------------------------------------------------------
// Open abc.zip, replace the content of the "b.txt" entry with something else, and re-write.
zip2 := CkZip_Create();
CkZip_OpenZip(zip2,'qa_output/abc.zip');

entry := CkZipEntry_Create();
if (CkZip_EntryOf(zip2,'b.txt',entry) = True) then
  begin
    CkZipEntry_ReplaceString(entry,'This is the new content.  bbbbbbbbbbbbbbbbbbbbbb','utf-8');
  end;

// Write the modified .zip back to "abc.zip"
success := CkZip_WriteZipAndClose(zip2);

Memo1.Lines.Add('success.');

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

end;