下面是一个来自w3学校的简单示例，它使用一点JS来复制输入字段的值。

<input type="text" value="StackExchange WordPress" id="myInput">
<button onclick="myFunction()">Copy text</button>

<p>The document.execCommand() method is not supported in IE9 and earlier.</p>

<script>
function myFunction() {
  var copyText = document.getElementById("myInput");
  copyText.select();
  document.execCommand("Copy");
  alert("Copied the text: " + copyText.value);
}    
</script>