PerformanceObserverEntryList

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The PerformanceObserverEntryList interface is a list of peformance events that were explicitly observed via the observe() method.

Note: this interface is exposed to Window and Worker.

Methods

PerformanceObserverEntryList.getEntries(): Returns a list of explicitly observed PerformanceEntry objects based on the given filter.
PerformanceObserverEntryList.getEntriesByType(): Returns a list of explicitly observed PerformanceEntry objects of the given entry type.
PerformanceObserverEntryList.getEntriesByName(): Returns a list of explicitly observed PerformanceEntry objects based on the given name and entry type.

Example

JavaScript

Copy Code

// Create observer for all performance event types 
// list is of type PerformanceObserveEntryList
var observe_all = new PerformanceObserver(function(list, obs) {  
   var perfEntries; 
   // Print all entries perfEntries = list.getEntries(); 
   for (var i=0; i < perfEntries.length; i++) { 
      print_perf_entry(perfEntries[i]); 
      // do something with it 
   }
}

Specifications

Specification	Status	Comment
Performance Timeline Time Level 2 The definition of 'PerformanceObserverEntryList' in that specification.	Editor's Draft	Initial definition.

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	52.0	49 (49)^[1]	No support	39	No support

Feature	Android	Android Webview	Firefox Mobile (Gecko)	IE Phone	Opera Mobile	Safari Mobile	Chrome for Android
Basic support	No support	No support	49.0 (49)^[1]	No support	39	No support	52.0

[1] Only activated in Nightly builds. Controlled by the dom.enable_performance_observer preference.

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/performanceobserverentrylist

API Interface Reference Web Performance