var template='<div class="m-modal">\       <div class="modal_align"></div>\       <div class="modal_wrap">\         <div class="bk"></div>\         <div class="modal_body">\           <h3>登錄網易云課堂</h3>\           <div class="form1">\             <input value="賬號">\           </div>\           <div class="form2">\             <input value="密碼">\           </div>\           <button class="submit">登錄</button>\         </div>\       </div>\     </div>' var container; function html2node(str){     container = document.createElement('div');     container.innerHTML = str;    return container.children[0]; } var _layout=html2node(template); var show=function(){   var asd=document.getElementById("parent");   asd.appendChild(_layout); } container.querySelector('.bk').addEventListener('click', function(event){     _layout.parentNode.removeChild(_layout); });在chrome中的調試面板中，為何container只有一個div元素，根據container.innerHTML = str;這句，應該顯示template元素??？