function getOpenid($step,$type='base',$backurl=null,$minwen=1,$app_id,$app_secret){
if(!is_weixin()) return false;
$cfg = array('appid'=>$app_id,'secret'=>$app_secret);
switch ($step) {
case '2':
$s = json_decode(getRemoteContent('https://api.weixin.qq.com/sns/oauth2/access_token?appid='.$cfg['appid'].'&secret='.$cfg['secret'].'&code='.$_GET['code'].'&grant_type=authorization_code'),true);
cookie(md5('share_openid'),$s['openid']);
$u = json_decode(getRemoteContent('https://api.weixin.qq.com/sns/userinfo?access_token='.$s['access_token'].'&openid='.$s['openid'].'&lang=zh_CN'),true);
if($u['errcode']){
$s['w_id'] = $w_id;
//处理手机的用户信息，没有昵称头像.....
}else{
$u['w_id'] = $w_id;
//处理手机的用户信息，带昵称头像.....
}
break;
default:
$url = "https://open.weixin.qq.com/connect/oauth2/authorize?appid=".$cfg['appid']."&redirect_uri=".urlencode($backurl)."&response_type=code&scope=snsapi_".$type."&state=1#wechat_redirect";
if($minwen){
$html = "<!doctype html><html><head></head><body>";
$html .= "<div style='font-size:2em;margin-top:40%;text-align:center;'>页面加载中，请稍候...</div><script>location.href='".$url."'</script>";
$html .= "</body></html>";
die($html);
}else{
@header("location:".$url);
}
}
}
