PerformanceElementTiming.identifier

The identifier read-only property of the PerformanceElementTiming interface returns the value of the elementtiming attribute on the element.

Value

A DOMString.

Examples

In this example the value of elementtiming is big-image. Calling entry.identifier therefore returns the string big-image.

<img src="image.jpg" alt="a nice image" elementtiming="big-image" id="myImage">

const observer = new PerformanceObserver((list) => {
  let entries = list.getEntries().forEach(function (entry) {
    if (entry.identifier === "big-image") {
      console.log(entry.naturalWidth);
    }
  });
});
observer.observe({ entryTypes: ["element"] });

Note: This example uses the PerformanceObserver interface to create a list of performance measurement events. In our case we observe the PerformanceEntry.entrytype element in order to use the PerformanceElementTiming interface.

Specifications

Specification
Element Timing API
# ref-for-dom-performanceelementtiming-identifier

Browser compatibility

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