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ToggleEvent: oldState property - Web APIs | MDN
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ToggleEvent: oldState property
Baseline
2023
Newly available
Since November 2023, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
The oldState read-only property of the ToggleEvent interface is a string representing the state the element is transitioning from.
Value
A string. Possible values are "open" (the popover is going from showing to hidden) or "closed" (the popover going from hidden to shown).
Examples
js
const popover = document.getElementById("mypopover");
// …
popover.addEventListener("beforetoggle", (event) => {
if (event.oldState === "open") {
console.log("Popover is being hidden");
} else {
console.log("Popover is being shown");
}
});
Specifications
| Specification |
|---|
| HTML # dom-toggleevent-oldstate |
Browser compatibility
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