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EventCounts - Web API | MDN
このインターフェイスにはコンストラクターがありません。通常は performance.eventCounts
プロパティを使用してこのオブジェクトのインスタンスを取得します。
以下は EventCounts
マップから情報を取得するいくつかの例です。マップは読み取り専用のため、 clear()
, delete()
, set()
メソッドは利用できないことに注意してください。
for (entry of performance.eventCounts.entries()) {
const type = entry[0];
const count = entry[1];
}
const clickCount = performance.eventCounts.get("click");
const isExposed = performance.eventCounts.has("mousemove");
const exposedEventsCount = performance.eventCounts.size;
const exposedEventsList = [...performance.eventCounts.keys()];