'end' 事件
'end'
事件来自 stream.Readable
类。
'end'
事件在所有数据输出后触发,该事件发生在调用 transform._flush()
中的回调之后。
在出现错误的情况下,不应触发 'end'
。
The 'end'
event is from the stream.Readable
class. The 'end'
event is
emitted after all data has been output, which occurs after the callback in
transform._flush()
has been called. In the case of an error,
'end'
should not be emitted.