PerformanceElementTiming.toJSON()

The toJSON() method of the PerformanceElementTiming interface is a standard serializer. It returns a JSON representation of the object's properties.

Syntax

var json = PerformanceElementTiming.toJSON();

Return value

json

A JSON object that is the serialization of the PerformanceElementTiming object.

Examples

In this example calling entry.toJSON() returns a JSON representation of the PerformanceElementTiming object, with the information about the image element.

<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.toJSON());
    }
  });
});
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

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
toJSON
77
79
No
No
64
No
77
77
No
55
No
12.0

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https://developer.mozilla.org/en-US/docs/Web/API/PerformanceElementTiming/toJSON