TEST
HeadTr.appendChild(CityTd);                            //NodeHead
HeadTr.appendChild(ValueTd);
HeadTr.appendChild(OpTd);
contact.appendChild(HeadTr);
console.log(contact);                                  
for( node in aqiData){                                  //NodeChild
    var Tr = document.createElement('tr');
    var NCityTd = document.createElement('td');
    var NValueTd = document.createElement('td');
    var DelTd = document.createElement('td');
    var Button = document.createElement('button');
    Button.innerHTML = 'del';
    NCityTd.innerHTML = node;
    NValueTd.innerHTML = aqiData[node];
    DelTd.appendChild(Button);
    Tr.appendChild(NCityTd);
    Tr.appendChild(NValueTd);
    Tr.appendChild(DelTd);
    contact.appendChild(Tr);  
}
The NodeChild is behind the console.log.
In my point,the console.log only output the NodeHead
why the console.log output the NodeChild

