步骤一,请求认证

https://open.weixin.qq.com/connect/oauth2/authorize?appid=xxx&redirect_uri=redirect_url&response_type=code&scope=snsapi_userinfo&state=xxx#wechat_redirect

步骤二:在回调接口里面调用网页授权

https://api.weixin.qq.com/sns/oauth2/component/access_token?appid=xxx&code=xxx&grant_type=authorization_code&component_appid=xxx&component_access_token=xxx

这一步就出问题了，返回40029

{"errcode":40029,"errmsg":"invalid code, rid: 642f71b3-72cff452-48c450c9"}