https://developers.weixin.qq.com/doc/offiaccount/Basic_Information/Get_access_token.html
code换取openid时,会出现重新redirect_url调用两次,导致openid为空
https://developers.weixin.qq.com/doc/offiaccount/Basic_Information/Get_access_token.html
code换取openid时,会出现重新redirect_url调用两次,导致openid为空