正确的方法是在URL后面简单地添加内容:

The correct way of doing this is to simply add the content after the URL:

c = Curl::Easy.http_post("https://example.com", json_string_goes_here   
    ) do |curl|
      curl.headers['Accept'] = 'application/json'
      curl.headers['Content-Type'] = 'application/json'
      curl.headers['Api-Version'] = '2.2'
    end

这会将json_string设置为请求正文.

This will set the json_string to be the request body.