Question

In Win7 RegEdit edit or view a binary just like 1A 2B 3C 4D
now I get a string

str := '1A,2B,3C,4D';

how to write str into Registry , and in Win7 RegEdit it display 1A 2B 3C 4D

Answer 1

var
  Data: array of Byte; // or whatever binary container you want to use
  Reg: TRegistry;
begin
  ...
  SetLength(Data, 4);
  Data[0] := $1A;
  Data[1] := $2B;
  Data[2] := $3C;
  Data[3] := $4D; 

  Reg := TRegistry.Create(KEY_SET_VALUE);
  try
    Reg.RootKey := ...;
    if Reg.OpenKey('...', True) then
    begin
      Reg.WriteBinaryData('Value', Data[0], 4);
      Reg.CloseKey;
    end;
  finally
    Reg.Free;
  end;
  ...
end;