创建和附加一个DOM元素与其它元素

Question

我的代码如下

;(function(window){ 
    var $description_window= document.querySelector('.mg_post_description'), 
     $headings= document.querySelectorAll('.mg_blog_main_content h3'), 
     $paragraph = document.createElement('p'); 
     for (var j = 0; j < $headings.length; j++) { 
      var $headingChildren=$headings[j].cloneNode(true).childNodes; 
      $paragraph.appendChild($headingChildren[j]); 
     } 
     $description_window.append($paragraph); 
})(window); 

这里就是我想要做的是内容;复制内容框的h3标签。然后创建一个paragraph元素。然后将p标签附加到收集的h3标签中。但是，在运行此操作时出现以下错误。

无法执行appendChild对Node：参数1不是Node类型。

;(function(window){ 
 
    var $description_window= document.querySelector('.post_description'), 
 
    
 
    $headings= document.querySelectorAll('.post_description h3'), 
 
    $paragraph = document.createElement('p'); 
 
    
 
    for (var j = 0; j < $headings.length; j++) { 
 
    
 
     var $headingChildren=$headings[j].cloneNode(true).childNodes; 
 
      $paragraph.appendChild($headingChildren[j]); 
 
     } 
 
     
 
     $description_window.append($paragraph); 
 
     
 
})(window);

.post_description{ 
 

 
    width:200px; 
 
    height:200px; 
 
    background-color:#555; 
 
    position:absolute; 
 
    top:10%; 
 
    right:8%; 
 
    
 
} 
 

 
.post_description a { 
 
    
 
    color:white; 
 
} 
 

 
.main_body{ 
 

 
    padding-top:40%; 
 

 
}

<div class="main_body"> 
 
    <h3>Testing one</h3> 
 
    <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.</p> 
 

 
    <h3>Testing two</h3> 
 
    <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.</p> 
 

 

 
    <h3>Testing three</h3> 
 

 
    <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.</p> 
 

 

 
    <h3>Testing four</h3> 
 

 
    <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.</p> 
 

 
</div> 
 

 
<div class="post_description"></div>

可能有人请解释为什么发生这种情况，如何解决这个

感谢

Answer 1

为了实现预期的结果，请使用下列选项

function addElem() { 
    var mElem = document.querySelector('.mg_post_description') 
    var hElems = document.getElementsByTagName('H3'); 
    var node = document.createElement("P"); 
    for (var i = 0; i < hElems.length; i++) { 

     var textnode = document.createTextNode(hElems[i].innerHTML); 
     var cloneElem = node.cloneNode(true); 
     cloneElem.appendChild(textnode); 
     mElem.appendChild(cloneElem); 
    } 
}; 

addElem() 

Codepen- https://codepen.io/nagasai/pen/YVEzdJ

Answer 2

var d = document.querySelector('.desc'), 
 
    h = document.querySelectorAll('.main h3'); 
 

 
h.forEach(function(n) { 
 
    var p = document.createElement('p'); 
 
    p.innerHTML = n.cloneNode(true).innerHTML || ''; 
 
    d.append(p); 
 
});

.desc { 
 
    color: red; 
 
}

<div class="main"> 
 
    <h3>First</h3> 
 
    <h3>Second</h3> 
 
    <h3>Third</h3> 
 
</div> 
 

 
<div class="desc"> 
 
</div>