The getEntries()
method of the PerformanceObserverEntryList
interface returns a list of explicitly observed performance entry objects. The list's members are determined by the set of entry types specified in the call to the observe()
method. The list is available in the observer's callback function (as the first parameter in the callback).
A list of explicitly observed PerformanceEntry
objects. The items will be in chronological order based on the entries' startTime
. If no objects are found, an empty list is returned.
The following example shows the difference between the getEntries()
, getEntriesByName()
, and getEntriesByType()
methods.
const observer = new PerformanceObserver((list, obs) => {
let perfEntries = list.getEntries();
perfEntries.forEach((entry) => {
console.log(`${entry.name}'s duration: ${entry.duration}`);
});
perfEntries = list.getEntriesByName("debugging", "measure");
perfEntries.forEach((entry) => {
console.log(`${entry.name}'s duration: ${entry.duration}`);
});
perfEntries = list.getEntriesByType("mark");
perfEntries.forEach((entry) => {
console.log(`${entry.name}'s startTime: ${entry.startTime}`);
});
});
observer.observe({
entryTypes: ["mark", "measure", "navigation", "resource"],
});