复制js的“准”正确用法

function kobe(id)
     {
          var targetText = document.getElementById(id);
          try
          {
                 var clipText = targetText.createTextRange();
                 clipText.execCommand("Copy");
                 alert("复制成功！");
          }
          catch(e)
          {
                 alert("您的浏览器不支持剪贴板复制，请手动记下群号：271816905！");
           }
     }

<input type="hidden" name="qqq" value="271816905" id="qqq"/>

<input type="button" value="复制" class="copy_btn" onclick="kobe('qqq');">