Object built-in object
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ObjectStatsWatcher

File Stats observation object

When the call fs.watchFile(target, onchange)is successful, an object of this type is returned

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var fs = require("fs");
var statsWatcher = fs.watchFile(target, (curStat, prevStat) => {
    // process
    // ...

    statsWatcher.unref();
});

Note that the onchange callback will be triggered when and only when the mtime attribute of the observed target file target changes.

Simply accessing the target file target will not trigger the onchange callback.

If fs.watchFile(target)the file or directory represented by target does not exist when calling , the onchange callback will not be called until the target is created. If the target file is deleted while the watcher is working, then There will be no subsequent callbacks.

inheritance relationship

%0 object object toString() toJSON() EventEmitter EventEmitter new EventEmitter() EventEmitter defaultMaxListeners on() addListener() prependListener() once() prependOnceListener() off() removeListener() removeAllListeners() setMaxListeners() getMaxListeners() listeners() listenerCount() eventNames() emit() object->EventEmitter StatsWatcher StatsWatcher onchange close() ref() unref() EventEmitter->StatsWatcher

static properties

defaultMaxListeners

Integer, the default global maximum number of listeners

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static Integer StatsWatcher.defaultMaxListeners;

member properties

onchange

Function, query and bind the "file change" event, equivalent to on("change", func);

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Function StatsWatcher.onchange;

member function

close

Stop observing the target file path and clear the reference count (no longer hold the process)

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StatsWatcher.close();

ref

Increase the reference count and tell fibjs not to exit the process as long as the watcher is still in use.

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StatsWatcher StatsWatcher.ref();

Return results:

  • StatsWatcher, returns StatsWatcher itself

The StatsWatcher obtained through fs.watchFile()has called this method by default, that is, it will hold the process by default.

unref

Decrement reference count

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StatsWatcher StatsWatcher.unref();

Return results:

  • StatsWatcher, returns StatsWatcher itself

on

Bind an event handler to the object

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Object StatsWatcher.on(String ev,
    Function func);

Call parameters:

  • ev: String, specifies the name of the event
  • func: Function, specify the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

Bind an event handler to the object

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Object StatsWatcher.on(Object map);

Call parameters:

  • map: Object, specifies the event mapping relationship, the object attribute name will be used as the event name, and the value of the attribute will be used as the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

addListener

Bind an event handler to the object

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Object StatsWatcher.addListener(String ev,
    Function func);

Call parameters:

  • ev: String, specifies the name of the event
  • func: Function, specify the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

Bind an event handler to the object

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Object StatsWatcher.addListener(Object map);

Call parameters:

  • map: Object, specifies the event mapping relationship, the object attribute name will be used as the event name, and the value of the attribute will be used as the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

prependListener

Bind an event handler to the object's origin

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Object StatsWatcher.prependListener(String ev,
    Function func);

Call parameters:

  • ev: String, specifies the name of the event
  • func: Function, specify the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

Bind an event handler to the object's origin

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Object StatsWatcher.prependListener(Object map);

Call parameters:

  • map: Object, specifies the event mapping relationship, the object attribute name will be used as the event name, and the value of the attribute will be used as the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

once

Bind a one-time event handler to the object. The one-time handler will only be triggered once.

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Object StatsWatcher.once(String ev,
    Function func);

Call parameters:

  • ev: String, specifies the name of the event
  • func: Function, specify the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

Bind a one-time event handler to the object. The one-time handler will only be triggered once.

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Object StatsWatcher.once(Object map);

Call parameters:

  • map: Object, specifies the event mapping relationship, the object attribute name will be used as the event name, and the value of the attribute will be used as the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

prependOnceListener

Bind an event handler to the object's origin

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Object StatsWatcher.prependOnceListener(String ev,
    Function func);

Call parameters:

  • ev: String, specifies the name of the event
  • func: Function, specify the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

Bind an event handler to the object's origin

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Object StatsWatcher.prependOnceListener(Object map);

Call parameters:

  • map: Object, specifies the event mapping relationship, the object attribute name will be used as the event name, and the value of the attribute will be used as the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

off

Unassign a function from the object processing queue

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Object StatsWatcher.off(String ev,
    Function func);

Call parameters:

  • ev: String, specifies the name of the event
  • func: Function, specify the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

Cancel all functions in the object processing queue

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Object StatsWatcher.off(String ev);

Call parameters:

  • ev: String, specifies the name of the event

Return results:

  • Object, returns the event object itself to facilitate chain calls

Unassign a function from the object processing queue

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Object StatsWatcher.off(Object map);

Call parameters:

  • map: Object, specifies the event mapping relationship, the object attribute name is used as the event name, and the value of the attribute is used as the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

removeListener

Unassign a function from the object processing queue

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Object StatsWatcher.removeListener(String ev,
    Function func);

Call parameters:

  • ev: String, specifies the name of the event
  • func: Function, specify the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

Cancel all functions in the object processing queue

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Object StatsWatcher.removeListener(String ev);

Call parameters:

  • ev: String, specifies the name of the event

Return results:

  • Object, returns the event object itself to facilitate chain calls

Unassign a function from the object processing queue

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Object StatsWatcher.removeListener(Object map);

Call parameters:

  • map: Object, specifies the event mapping relationship, the object attribute name is used as the event name, and the value of the attribute is used as the event processing function

Return results:

  • Object, returns the event object itself to facilitate chain calls

removeAllListeners

Cancels all listeners for all events from the object's processing queue. If an event is specified, removes all listeners for the specified event.

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Object StatsWatcher.removeAllListeners(String ev);

Call parameters:

  • ev: String, specifies the name of the event

Return results:

  • Object, returns the event object itself to facilitate chain calls

Cancels all listeners for all events from the object's processing queue. If an event is specified, removes all listeners for the specified event.

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Object StatsWatcher.removeAllListeners(Array evs = []);

Call parameters:

  • evs: Array, specify the name of the event

Return results:

  • Object, returns the event object itself to facilitate chain calls

setMaxListeners

The default limit on the number of listeners, for compatibility only

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StatsWatcher.setMaxListeners(Integer n);

Call parameters:

  • n: Integer, specify the number of events

getMaxListeners

Gets the default limit number of listeners, for compatibility only

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Integer StatsWatcher.getMaxListeners();

Return results:

  • Integer, returns the default limit quantity

listeners

Query the listener array for the specified event of the object

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Array StatsWatcher.listeners(String ev);

Call parameters:

  • ev: String, specifies the name of the event

Return results:

  • Array, returns the listener array for the specified event

listenerCount

Query the number of listeners for the specified event of the object

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Integer StatsWatcher.listenerCount(String ev);

Call parameters:

  • ev: String, specifies the name of the event

Return results:

  • Integer, returns the number of listeners for the specified event

Query the number of listeners for the specified event of the object

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Integer StatsWatcher.listenerCount(Value o,
    String ev);

Call parameters:

  • o: Value, specifies the object of the query
  • ev: String, specifies the name of the event

Return results:

  • Integer, returns the number of listeners for the specified event

eventNames

Query listener event name

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Array StatsWatcher.eventNames();

Return results:

  • Array, returns an array of event names

emit

Actively trigger an event

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Boolean StatsWatcher.emit(String ev,
    ...args);

Call parameters:

  • ev: String, event name
  • args: ..., event parameters will be passed to the event processing function

Return results:

  • Boolean, returns the event trigger status, returns true if there is a response event, otherwise returns false

toString

Returns the string representation of the object. Generally, "[Native Object]" is returned. The object can be re-implemented according to its own characteristics.

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String StatsWatcher.toString();

Return results:

  • String, returns the string representation of the object

toJSON

Returns a JSON format representation of the object, generally returning a collection of readable properties defined by the object.

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Value StatsWatcher.toJSON(String key = "");

Call parameters:

  • key: String, not used

Return results:

  • Value, returns a value containing JSON serializable
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