Delphi URLEncode 和urlDecode 转码

一、UrlEncode

function URLEncode(const msg: String): String;
var
   I : Integer;
begin
   Result := '';
   for I := 1 to Length(msg) do begin
       if msg[I] = ' ' then
           Result := Result + '+'
       else if msg[I] in ['a'..'z', 'A'..'Z', '0'..'9'] then
           Result := Result + msg[I]
       else
           Result := Result + '%' + IntToHex(ord(msg[I]), 2);
   end;
  ShowMessage(result);
end;

 二、UrlDecode

function urlDecode(url: string): string;
var i, s, g: Integer;
begin
  Result :='';

  for i := 1 to Length(url) do
  begin

    if url[i] = '%' then
    begin
      s := StrtoInt('$' + url[i + 1]) * 16;
      g := StrtoInt('$' + url[i + 2]);

      Result := Result + Chr(s + g);
    end
    else if not (((url[i - 1] = '%') and (url[i + 1] <> '%')) or ((url[i - 2] = '%') and (url[i - 1] <> '%') and (url[i + 1] = '%')) or ((url[i - 2] = '%') and (url[i - 1] <> '%') and (url[i + 1] <> '%'))) then
      Result := Result + url[i];

  end;
  ShowMessage(Result);
end;