根据我在错误描述中看到的内容，问题可能是您需要先将xml中的\r\n删除，然后再将其添加到url中. .别忘了还要对其进行url编码.

According what I see on the error description, the problem could be that you need to remove \r\n from the xml before adding it to the url. Don't forget also to url encode it.