performance.getEntriesByType()
The getEntriesByType()
method returns a list of
PerformanceEntry
objects for a given type. The list's members
(entries) can be created by making performance marks or
measures (for example by calling the mark()
method) at explicit points in time.
Note: This feature is available in Web Workers
Syntax
entries = window.performance.getEntriesByType(type);
Arguments
- type
-
The type of entry to retrieve such as "
mark
". The valid entry types are listed inPerformanceEntry.entryType
.
Return value
- entries
-
A list of
PerformanceEntry
objects that have the specifiedtype
. The items will be in chronological order based on the entries'startTime
. If no objects have the specifiedtype
, or no argument is provided, an empty list is returned.
Example
function usePerformanceEntryMethods() {
log("PerformanceEntry tests ...");
if (performance.mark === undefined) {
log("... performance.mark Not supported");
return;
}
// Create some performance entries via the mark() method
performance.mark("Begin");
doWork(50000);
performance.mark("End");
performance.mark("Begin");
doWork(100000);
performance.mark("End");
doWork(200000);
performance.mark("End");
// Use getEntries() to iterate through the each entry
var p = performance.getEntries();
for (var i=0; i < p.length; i++) {
log("Entry[" + i + "]");
checkPerformanceEntry(p[i]);
}
// Use getEntries(name, entryType) to get specific entries
p = performance.getEntries({name : "Begin", entryType: "mark"});
for (var i=0; i < p.length; i++) {
log("Begin[" + i + "]");
checkPerformanceEntry(p[i]);
}
// Use getEntriesByType() to get all "mark" entries
p = performance.getEntriesByType("mark");
for (var i=0; i < p.length; i++) {
log ("Mark only entry[" + i + "]: name = " + p[i].name +
"; startTime = " + p[i].startTime +
"; duration = " + p[i].duration);
}
// Use getEntriesByName() to get all "mark" entries named "Begin"
p = performance.getEntriesByName("Begin", "mark");
for (var i=0; i < p.length; i++) {
log ("Mark and Begin entry[" + i + "]: name = " + p[i].name +
"; startTime = " + p[i].startTime +
"; duration = " + p[i].duration);
}
}
Specifications
Specification |
---|
Performance Timeline # dom-performance-getentriesbytype |
Browser compatibility
BCD tables only load in the browser