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

Specification
Resource Timing Level 2 (Resource Timing 2)
# dom-performanceresourcetiming-initiatortype

Browser compatibility

BCD tables only load in the browser