var num = -1
var o = {
  '1': 1,
  'b': 'b',
  '3': 3,
  '0': 0,
  [num]: '-1',
  false: false,
  'a': 'a',
  'aa': 'aa',
  '哈哈': 'hh',
  '2': 2,
  '22': 22,
  '21': 21,
  '05': 2,
  '04': 1
}
var oUl = document.createElement('ul')
var oFragments =  document.createDocumentFragment()
for (var key in o) {
  var Li = document.createElement('li')
  Li.appendChild(document.createTextNode(key))
  oFragments.appendChild(Li)
  console.log(key)
}
oUl.appendChild(oFragments)
document.querySelector('body').appendChild(oUl)
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