如何在对话框中添加div？

<div id="dialog">
  <!-- 对话框内容 -->
</div>

#dialog {
  width: 300px;
  height: 200px;
  background-color: #f2f2f2;
}

<div id="dialog">
  <h2>对话框标题</h2>
  <p>对话框内容</p>
  <button>确定</button>
</div>

var dialog = document.getElementById("dialog");
var button = document.getElementById("button");

button.addEventListener("click", function() {
  dialog.style.display = "block";
});