问题
For certain videos the call to commentThreads does not return the complete set of toplevelcomments. For example the following call only returns 16 toplevel comments when in fact the video has over 3458 total comments, and the toplevel comments are clearly more than 16.
https://www.googleapis.com/youtube/v3/commentThreads?part=snippet&videoId=h_9-3Fj3ZdI&key=[KEY]&maxResults=50
I have run into this issue on a couple of Videos and in both cases the result seems to break on a comment which is in fact missing from the web UI. I have looked around and and tried multiple ways (i.e. trying to skip using start-index etc) , but I haven't found a solution. You can verify the missing comment in the the above result: 'z131gd2gwqnby3lea23byp3yyt3pshcqb04'
来源：https://stackoverflow.com/questions/33399772/youtube-data-api-v3-comment-threads-request-doesnt-return-all-comments