String Compress /Decompress

uses ZLib;

(*
* CompressString() usage:
*
* CompressedString := CompressString(DataString);
*)
function CompressString(const S: string) : string;
var
 InputStream: TCompressionStream;
 OutputStream: TMemoryStream;
 Size: Integer;
begin
 OutputStream := TMemoryStream.Create;

 try
   InputStream := TCompressionStream.Create(clMax, OutputStream);
   try
     Size := Length(S);
     InputStream.Write(Size, SizeOf(Size));
     InputStream.Write(S[1], Size)
   finally
     InputStream.Free
   end;

   SetLength(Result, OutputStream.Size);
   OutputStream.Seek(0, soFromBeginning);
   OutputStream.Read(Result[1], Length(Result))

 finally
   OutputStream.Free
 end
end;

(*
* DecompressString() usage:
*
* DataString := DecompressString(CompressedString);
*)
function DecompressString(const S: string) : string;
var
 InputStream: TMemoryStream;
 OutputStream: TDecompressionStream;
 Size: Integer;
begin
 InputStream := TMemoryStream.Create;

 try
   InputStream.Write(S[1], Length(S));
   InputStream.Seek(0, soFromBeginning);

   OutputStream := TDecompressionStream.Create(InputStream);
   try
     OutputStream.Read(Size, SizeOf(Size));
     SetLength(Result, Size);
     OutputStream.Read(Result[1], Size)

   finally
     OutputStream.Free
   end

 finally
   InputStream.Free
 end
end;