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Delphi DLL

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 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, Crypt2, FileAccess;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
crypt: HCkCrypt2;
ivHex: PWideChar;
keyHex: PWideChar;
dataFile: PWideChar;
outFile: PWideChar;
outFile2: PWideChar;
fac: HCkFileAccess;
bEqual: Boolean;

begin
success := False;

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

crypt := CkCrypt2_Create();

CkCrypt2_putCryptAlgorithm(crypt,'aes');
CkCrypt2_putCipherMode(crypt,'cbc');
CkCrypt2_putKeyLength(crypt,128);
CkCrypt2_putPaddingScheme(crypt,0);

ivHex := '000102030405060708090A0B0C0D0E0F';
CkCrypt2_SetEncodedIV(crypt,ivHex,'hex');

keyHex := '00010203040506071011121314151617';
CkCrypt2_SetEncodedKey(crypt,keyHex,'hex');

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

success := CkCrypt2_CkEncryptFile(crypt,dataFile,outFile);
success := CkCrypt2_CkDecryptFile(crypt,outFile,outFile2);

fac := CkFileAccess_Create();
bEqual := CkFileAccess_FileContentsEqual(fac,dataFile,outFile2);
if (bEqual <> True) then
  begin
    Memo1.Lines.Add('Decrypted file not equal to the original.');
  end
else
  begin
    Memo1.Lines.Add('Success.');
  end;

CkCrypt2_Dispose(crypt);
CkFileAccess_Dispose(fac);

end;