代码示例:(标识:jsck_prompt_1)
<!DOCTYPE html>
<html>
<body>

<h1>Window 对象</h1>

<h2>prompt() 方法</h2>

<p>请点击按钮来演示提示框。</p>

<button onclick="myFunction()">试一试</button>

<p id="demo"></p>

<script>
function myFunction() {
  let person = prompt("请输入你的名字", "哈利·波特");
  if (person != null) {
    document.getElementById("demo").innerHTML =
    "Hello " + person + "!您今天怎么样?";
  }
}
</script>

</body>
</html>
运行结果: