前端複製指定標籤中的文字

<tr>
    <td>URL(伺服器地址)</td>
    <td class="apiUrl"><span id="apiUrl">{$mp.url}</span><span class="tip1 rha-bt-a"></span></td>
    <td><a href="javascript:;" onclick="BtnClick('apiUrl','.tip1')" class="rha-bt-a">複製</a></td>
</tr>
 

<script type="text/javascript">
    function copyText(text) {
        var textarea = document.createElement("textarea");
        var currentFocus = document.activeElement;
        document.body.appendChild(textarea);
        textarea.value = text;
        textarea.focus();
        if (textarea.setSelectionRange)
            textarea.setSelectionRange(0, textarea.value.length);
        else
            textarea.select();
        try {
            var flag = document.execCommand("copy");
        } catch (eo) {
            var flag = false;
        }
        document.body.removeChild(textarea);
        currentFocus.focus();
        return flag;
    }
    function BtnClick(name,tip) {
        var a = document.getElementById(name).innerHTML;
        var flag = copyText(a);//這個必須在DOM物件的事件執行緒中執行
        var textlog = flag ? "複製成功！" : "複製失敗！";
        //展示後2秒消失
        $(tip).fadeIn();
        $(tip).insertAfter($(tip)).html(textlog).fadeOut(2000);
    };
</script>