uses System.Net.URLClient,System.Net.HttpClient, System.Net.HttpClientComponent;

function HttpPost(Url: String; ID: Integer; Cookie: string): String;

  var

  NetHttp: TNetHTTPClient;

  TmpSS: TStringStream;

  ParmList: TStringList;

begin

  Result := '';

  NetHttp := TNetHTTPClient.Create(nil);

  ParmList := TStringList.Create;

  TmpSS := TStringStream.Create('', TEncoding.UTF8);

  try

    //NetHttp.Asynchronous := True;  异步

    NetHttp.ConnectionTimeout := 10000;

    NetHttp.ResponseTimeout := 20000;

   // NetHttp.CustomHeaders['Cookie'] := 'sscSESSID=' + Cookie;

    NetHttp.UserAgent := 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36';

    ParmList.Add('op=getCurIssue');

    ParmList.Add('op=getCurIssue');

    ParmList.Add('lotteryId=' + IntToStr(ID));

    NetHttp.Post(Url, ParmList, TmpSS);

    Result := Trim(TmpSS.DataString);

  finally

    NetHttp.Free;

    ParmList.Free;

    TmpSS.Free;

  end;

end;

procedure TForm1.BitBtn1Click(Sender: TObject);

begin

Memo1.Text:= HttpPost('http://www.baidu.com/',1,'123');

end;