(Delphi ActiveX) AES Encrypt String (utf-8 byte representation) and return Base64

Demonstrates how to AES encrypt the utf-8 byte representation of a string and return in base64 format.

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

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
crypt: TChilkatCrypt2;
ivHex: WideString;
keyHex: WideString;
encryptedStr: WideString;
urlEncoded: WideString;
encBase64Url: WideString;
encBase64: WideString;
originalStr: WideString;

begin
// This example 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 := 256;
crypt.Charset := 'utf-8';
crypt.EncodingMode := 'base64';

ivHex := '000102030405060708090A0B0C0D0E0F';
crypt.SetEncodedIV(ivHex,'hex');
keyHex := '000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F';
crypt.SetEncodedKey(keyHex,'hex');

encryptedStr := crypt.EncryptStringENC('This is the original string');
Memo1.Lines.Add(encryptedStr);

// Let's say we want to URL encode the base64 string..
crypt.CryptAlgorithm := 'none';
crypt.EncodingMode := 'url';
urlEncoded := crypt.EncryptStringENC(encryptedStr);
Memo1.Lines.Add(urlEncoded);

// Sample output:

//  q3fmgEqjqa9o//ZS6aPuh4Wtbrrxx/WOIQSKeVnesZg=
//  q3fmgEqjqa9o%2F%2FZS6aPuh4Wtbrrxx%2FWOIQSKeVnesZg%3D

// -------------------------------------------------------------------
// Now let's do the reverse...
// 

// We start with a string that is the binary encrypted data, base64 encoded, and then URL encoded.
encBase64Url := 'q3fmgEqjqa9o%2F%2FZS6aPuh4Wtbrrxx%2FWOIQSKeVnesZg%3D';

// We'll use the same crypt object.  If using a new instance of the crypt object,
// make sure *all* settings are identical:  the algorithm, cipher mode, key length, charset, encoding mode, IV, and secret key.

// Decode from URL...
crypt.CryptAlgorithm := 'none';
crypt.EncodingMode := 'url';
encBase64 := crypt.DecryptStringENC(urlEncoded);
Memo1.Lines.Add(encBase64);

// Now decrypt...
crypt.CryptAlgorithm := 'aes';
crypt.EncodingMode := 'base64';
originalStr := crypt.DecryptStringENC(encBase64);
Memo1.Lines.Add(originalStr);
end;