Calculate MD5 Hash of File (or SHA-1, and other hash algorithms)

Demonstrates how to calculate a hash for a file's contents.

Download Chilkat Crypt ActiveX

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls,
    CHILKATCRYPT2Lib_TLB,
    OleCtrls;

...

procedure TForm1.Button1Click(Sender: TObject);
var
crypt: TChilkatCrypt2;
success: Integer;
hashStr: String;

begin
crypt := TChilkatCrypt2.Create(Self);

success := crypt.UnlockComponent('Anything for 30-day trial');
if (success <> 1) then
  begin
    Memo1.Lines.Add(crypt.LastErrorText);
    Exit;
  end;

//  Set the name of the hash algorithm.
//  Other choices include "sha1", "sha384", "sha512", "md2", "md5", and "haval".
crypt.HashAlgorithm := 'md5';

//  EncodingMode specifies the encoding of the hash output.
//  It may be "hex", "url", "base64", or "quoted-printable".
crypt.EncodingMode := 'hex';

//  Files of any type may be hashed -- it doesn't matter
//  if the file is binary or text...

hashStr := crypt.HashFileENC('/temp/something.dat');
if (Length(hashStr) = 0 ) then
  begin
    Memo1.Lines.Add(crypt.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add(hashStr);
end;