小弟我用MFC模拟登录网页,登录不成功,请大家帮小弟我看下代码错在哪里

我用MFC模拟登录网页,登录不成功,请大家帮我看下代码错在哪里
这是获取到的POST包:

POST /member.php?mod=logging&action=login&loginsubmit=yes&infloat=yes&lssubmit=yes&inajax=1 HTTP/1.1
Accept: image/jpeg, application/x-ms-application, image/gif, application/xaml+xml, image/pjpeg, application/x-ms-xbap, */*
Referer: http://club.topsage.com/
Accept-Language: zh-CN
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; QQDownload 717; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E)
Content-Type: application/x-www-form-urlencoded
Accept-Encoding: gzip, deflate
Host: club.topsage.com
Content-Length: 67
Connection: Keep-Alive
Cache-Control: no-cache
Cookie: __utmc=191887663; pgv_info=ssi=s7023552968; Hm_lpvt_ee0d63d2db0dfbf9e0d399bccbd5fce7=1375031866; __utma=191887663.1831613117.1375031859.1375031859.1375031859.1; __utmb=191887663.1.10.1375031859; __utmz=191887663.1375031859.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); tsclub_bb90_saltkey=Is0eyMnm; tsclub_bb90_lastvisit=1375028263; tsclub_bb90_sid=xEXwfN; tsclub_bb90_lastact=1375031863%09home.php%09misc; tsclub_bb90_sendmail=1; pgv_pvi=775373824; Hm_lvt_ee0d63d2db0dfbf9e0d399bccbd5fce7=1375031686

username=AndyLee123&password=zbt13579&quickforward=yes&handlekey=ls


这是获取的登录地址:

http://club.topsage.com/member.php?mod=logging&action=login&loginsubmit=yes&infloat=yes&lssubmit=yes&inajax=1


我使用的账号是:
用户名:AndyLee123
密码:zbt13579

我的代码是这样写的:

CInternetSession session;
CHttpConnection *pConnection;
CHttpFile* pHttpFile;
CString data = "username=AndyLee123&password=zbt13579&quickforward=yes&handlekey=ls";
try
{
pConnection = session.GetHttpConnection("club.topsage.com",CHttpConnection::HTTP_VERB_POST,80);
pHttpFile = pConnection->OpenRequest(CHttpConnection::HTTP_VERB_POST,"/member.php?mod=logging&action=login&loginsubmit=yes&infloat=yes&lssubmit=yes&inajax=1");
pHttpFile -> AddRequestHeaders("POST /member.php?mod=logging&action=login&loginsubmit=yes&infloat=yes&lssubmit=yes&inajax=1 HTTP/1.1");
pHttpFile -> AddRequestHeaders("Accept: image/jpeg, application/x-ms-application, image/gif, application/xaml+xml, image/pjpeg, application/x-ms-xbap, */*");
pHttpFile -> AddRequestHeaders("Referer: http://club.topsage.com/");