ClipboardJS实现点击复制功能

1. <script src="//lib.baomitu.com/clipboard.js/1.7.1/clipboard.min.js"></script>
2. <!-- Target -->
   <input id="foo" value="https://github.com/zenorocha/clipboard.js.git">

   <!-- Trigger -->
   <button class="btn" data-clipboard-target="#foo">
   Copy to clipboard
   </button>

3. var clipboard = new ClipboardJS('#foo');
   clipboard.on('success', function(e) {
   console.log(e);
   });
   clipboard.on('error', function(e) {
   console.log(e);
   });