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Delphi ActiveX

Encrypt / Decrypt a File and Verify it has not Changed

See more Encryption Examples

Demonstrates how to encrypt and decrypt a file, and verify it has not changed.

Chilkat Delphi ActiveX Downloads

Delphi ActiveX
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
crypt: TChilkatCrypt2;
ivHex: WideString;
keyHex: WideString;
dataFile: WideString;
outFile: WideString;
outFile2: WideString;
fac: TCkFileAccess;
bEqual: Integer;

begin
success := 0;

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

crypt := TChilkatCrypt2.Create(Self);

crypt.CryptAlgorithm := 'aes';
crypt.CipherMode := 'cbc';
crypt.KeyLength := 128;
crypt.PaddingScheme := 0;

ivHex := '000102030405060708090A0B0C0D0E0F';
crypt.SetEncodedIV(ivHex,'hex');

keyHex := '00010203040506071011121314151617';
crypt.SetEncodedKey(keyHex,'hex');

dataFile := 'qa_data/zips/HBIQ040615300005.ZIP';
outFile := 'qa_output/HBIQ040615300005.enc';
outFile2 := 'qa_output/HBIQ040615300005.ZIP';

success := crypt.CkEncryptFile(dataFile,outFile);
success := crypt.CkDecryptFile(outFile,outFile2);

fac := TCkFileAccess.Create(Self);
bEqual := fac.FileContentsEqual(dataFile,outFile2);
if (bEqual <> 1) then
  begin
    Memo1.Lines.Add('Decrypted file not equal to the original.');
  end
else
  begin
    Memo1.Lines.Add('Success.');
  end;
end;