Anexar JavaScript HTML bruto

function appendHtml(el, str) {
  var div = document.createElement('div');
  div.innerHTML = str;
  while (div.children.length > 0) {
    el.appendChild(div.children[0]);
  }
}
var html = '<h1 id="title">Some Title</h1><span style="display:inline-block; width=100px;">Some arbitrary text</span>';
appendHtml(document.body, html); // "body" has two more children - h1 and span.
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