web api instance property
ToggleEvent: oldState property
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
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
SpecificationsStandards references are available on the canonical MDN page.
Browser compatibility
Browser compatibilityCompatibility data is available on the canonical MDN page.