PerformanceResourceTiming.initiatorType

The initiatorType read-only property is a string that represents the type of resource that initiated the performance event.

The value of this string is as follows:

  • If the initiator is a Element, the property returns the element's localName.
  • If the initiator is a CSS resource, the property returns "css".
  • If the initiator is a XMLHttpRequest object, the property returns "xmlhttprequest".
  • If the initiator is a PerformanceNavigationTiming object, the property returns an empty string ("").

Note: This feature is available in Web Workers

Syntax

resource.initiatorType;

Return value

A string representing the type of resource that initiated the performance event, as specified above.

Example

function print_PerformanceEntries() {
  // Use getEntriesByType() to just get the "resource" events
  var p = performance.getEntriesByType("resource");
  for (var i=0; i < p.length; i++) {
    print_initiatorType(p[i]);
  }
}
function print_initiatorType(perfEntry) {
  // Print this performance entry object's initiatorType value
  var value = "initiatorType" in perfEntry;
  if (value)
    console.log("... initiatorType = " + perfEntry.initiatorType);
  else
    console.log("... initiatorType = NOT supported");
}

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
initiatorType
43
12
40
No
30
11
43
43
42
30
11
4.0

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https://developer.mozilla.org/en-US/docs/Web/API/PerformanceResourceTiming/initiatorType