PerformanceScriptTiming: toJSON() method
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Experimental: This is an experimental technology
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The toJSON() method of the PerformanceScriptTiming interface is a serializer; it returns a JSON representation of the PerformanceScriptTiming object.
Syntax
toJSON()
Parameters
None.
Return value
A JSON object that is the serialization of the PerformanceScriptTiming object.
Examples
Using the toJSON method
In this example, calling entry.toJSON() returns a JSON representation of the first PerformanceScriptTiming object available in an observed long animation frame.
const observer = new PerformanceObserver((list) => {
list.getEntries().forEach((entry) => {
console.log(entry.scripts[0].toJSON());
});
});
observer.observe({ type: "long-animation-frame", buffered: true });
This would log an object like so:
({
duration: 45,
entryType: "script",
executionStart: 11803.199999999255,
forcedStyleAndLayoutDuration: 0,
invoker: "DOMWindow.onclick",
invokerType: "event-listener",
name: "script",
pauseDuration: 0,
sourceURL: "https://web.dev/js/index-ffde4443.js",
sourceFunctionName: "myClickHandler",
sourceCharPosition: 17796,
startTime: 11803.199999999255,
windowAttribution: "self",
});
To get a JSON string, you can use JSON.stringify(entry) directly; it will call toJSON() automatically.
Specifications
| Specification |
|---|
| Long Animation Frames API # dom-performancescripttiming-tojson |
Browser compatibility
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