utils/uutlConversion.pas

unit uutlConversion;

{ Package:      Utils
  Prefix:       utl - UTiLs
  Beschreibung: diese Unit stellt Methoden für Konvertierung verschiedener Datentypen zur Verfügung }

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils;

function Supports(const aInstance: TObject; const aClass: TClass; out aObj): Boolean; overload;
function HexToBinary(HexValue: PChar; BinValue: PByte; BinBufSize: Integer): Integer;

implementation

function Supports(const aInstance: TObject; const aClass: TClass; out aObj): Boolean;
begin
  result := Assigned(aInstance) and aInstance.InheritsFrom(aClass);
  if result then
    TObject(aObj) := aInstance
  else
    TObject(aObj) := nil;
end;


////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//wandelt einen Hex-String in einen Blob um
//@hexvalue: Hex-String
//@binvalue: Zeiger auf einen Speicherbereich
//@binbufsize: maximale größe die geschrieben werden darf
//@result: gelesene bytes
function HexToBinary(HexValue: PChar; BinValue: PByte; BinBufSize: Integer): Integer;
var i,j,h,l : integer;

begin
  i:=binbufsize;
  while (i>0) do
    begin
    if hexvalue^ IN ['A'..'F','a'..'f'] then
      h:=((ord(hexvalue^)+9) and 15)
    else if hexvalue^ IN ['0'..'9'] then
      h:=((ord(hexvalue^)) and 15)
    else
      break;
    inc(hexvalue);
    if hexvalue^ IN ['A'..'F','a'..'f'] then
      l:=(ord(hexvalue^)+9) and 15
    else if hexvalue^ IN ['0'..'9'] then
      l:=(ord(hexvalue^)) and 15
    else
      break;
    j := l + (h shl 4);
    inc(hexvalue);
    binvalue^:=j;
    inc(binvalue);
    dec(i);
    end;
  result:=binbufsize-i;
end;


end.