HTMLDialogElement：close 事件

addEventListener("close", (event) => { })

onclose = (event) => { }

<dialog class="example-dialog">
  <form method="dialog">
    <button>透過 method="dialog" 關閉</button>
  </form>
  <button class="close">透過 .close() 方法關閉</button>
  <p>或按下 <kbd>Esc</kbd> 鍵</p>
</dialog>

<button class="open-dialog">開啟對話方塊</button>

<div class="result"></div>

button,
div {
  margin: 0.5rem;
}

const result = document.querySelector(".result");

const dialog = document.querySelector(".example-dialog");
dialog.addEventListener("close", (event) => {
  result.textContent = "對話方塊已關閉";
});

const openDialog = document.querySelector(".open-dialog");
openDialog.addEventListener("click", () => {
  dialog.showModal();
  result.textContent = "";
});

const closeButton = document.querySelector(".close");
closeButton.addEventListener("click", () => {
  dialog.close();
});