Promise.<Response> - @see Response
- when init.body is set and init.method is either "GET" or "HEAD".
- when either network error or network time-out occurs after a http request is made.
- when there is a failure in reading files in FormData during posting FormData.
||either the URL string to connect with or a Request object having the URL and the init option in the below.|
||custom options for a HTTP request.|
||the HTTP request method.|
||the HTTP request headers to add.|
||the body that is included in the HTTP request body. There is a caveat for sending a FormData object. @see XMLHttpRequest.send.|
||indicates whether to send cookies. Possible values and functions are as follows: "omit" : cookies are NOT sent, "same-origin" and "include" : cookies are sent.|