<html>
<body>
<h3>以下实例演示了如何访问搜索框字段</h3>
<input type="search" id="mySearch" placeholder="Search for something..">
<p>点击按钮获取搜索字段的预期值的提示信息。</p>
<button onclick="myFunction()">点我</button>
<p id="demo"></p>
<script>
function myFunction() {
var x = document.getElementById("mySearch").placeholder;
document.getElementById("demo").innerHTML = x;
}
</script>
</body>
</html>