TimeRanges interface is used to represent a set of time ranges, primarily for the purpose of tracking which portions of media have been buffered when loading it for use by the <audio> and <video> elements.TimeRanges object includes one or more ranges of time, each specified by a starting and ending time offset. You reference each time range by using the start() and end() methods, passing the index number of the time range you want to retrieve.Returns an unsigned long representing the number of time ranges represented by the time range object.
Promise<number>Returns the time for the end of the specified range.
number. index is the range number to return the ending time for.Promise<number>Returns the time for the start of the range with the specified index.
number. index is the range number to return the starting time for.Promise<number>