真的没人能解答这个问题吗

Question

我用同一个idhttp组建，执行GET和POST操作，GET没问题，POST始终不对（获取数据包，失踪header不正确），请高手执教 
procedure TForm1.Button1Click(Sender: TObject); 
var 
  xx:string; 
  xxx:tstrings; 
  yy:TMemoryStream; 
  jpg:Tjpegimage; 
begin 
  idhttp1.Request.Connection:='Keep-Alive'; 
  idhttp1.Request.CacheControl:='no-cache'; 
  xxx:=tstringlist.Create; 
  yy := TMemoryStream.Create ; 
  xx:=IdHTTP1.Get('http://login.tom.com/captcha/drawme.php?type=6'); 
  xxx:=SplitString(xx,'='); 
  IdHTTP1.Get('http://login.tom.com/captcha/draw.php?post_key='+stringreplace(xxx[8],';expires','',[rfReplaceAll])+'&type=6',yy); 
  if StreamType(yy)='JPEG' then begin 
    yy.Position:=0; 
    try 
      Jpg:=tjpegimage.Create; 
      Jpg.LoadFromStream(yy); 
      image1.Picture.Graphic:= Jpg; 
    finally 
      Jpg.Free; 
    end; 
  end else if StreamType(yy)='BMP' then begin 
    yy.Position:=0; 
    image1.Picture.Bitmap.LoadFromStream(yy); 
  end else if StreamType(yy)='PNG' then begin 
    
  end; 
end; procedure TForm1.Button2Click(Sender: TObject); 
var 
  ParaList:tStringList; 
  str:string; 
begin 
  ParaList:=tstringlist.Create; 
  idhttp1.Request.Connection:='Keep-Alive'; 
  idhttp1.Request.CacheControl:='no-cache'; 
  idhttp1.request.contenttype:='application/x-www-form-urlencoded'; 
  try 
    ParaList.Add('funcid=reguser'); 
    ParaList.Add('rf=060702'); 
    ParaList.Add('refer=http://mail.tom.com'); 
    ParaList.Add('year=1980'); 
    ParaList.Add('month=1'); 
    ParaList.Add('day=1'); 
    ParaList.Add('uid=fsdads35sdf'); 
    ParaList.Add('password=111111qq'); 
    ParaList.Add('confirm_password=111111qq'); 
    ParaList.Add('[email protected]'); 
    ParaList.Add('authcode='+edit1.Text); 
    ParaList.Add('argee=1'); 
  str:=idhttp1.Post('http://bjcgi.tom.com/cgi-bin/tom_reg.cgi?rf=060702',paralist); 
  WB_LoadHTML(WebBrowser1,str); 
  finally 
    ParaList.Free; 
  end; end; 以上代码同样设置idhttp1.Request.Connection:='Keep-Alive'; 
但是GET获取的数据包header是正确的Connection: Keep-Alive，但是POST获取的数据包确是Connection: close，包括idhttp1.Request.CacheControl:='no-cache';也没有生效