替换html元素

<div id='divContainer'>
<div id='divBeReplaced'>被替换的元素</div>
</div>

var elemOld = document.getElementById('divBeReplaced');
var elemParent = elemOld.parentNode;
var elemNew = document.createElement('div');
elemNew.innerHTML = '新的元素';
elemParent.replaceChild(elemNew, elemOld);

$("#divBeReplaced").replaceWith("<b>Hello world!</b>");