[angvelem]

1.

Код:

function StrToOem(const AnsiStr: string): string;
begin
  SetLength(Result, Length(AnsiStr));
  if Length(Result) > 0 then
    CharToOemBuff(PChar(AnsiStr), PChar(Result), Length(Result));
end;

function OemToAnsiStr(const OemStr: string): string;
begin
  SetLength(Result, Length(OemStr));
  if Length(Result) > 0 then
    OemToCharBuff(PChar(OemStr), PChar(Result), Length(Result));
end;

2. Pos, PosEx