<script>
var textDiv = document.createElement("div");
var isElement = function(obj){
if(obj && obj.nodeType === 1){
if(window.Node && (obj instanceof Node)){
return true;
}
try{
testDiv.appendChild(obj);
testDiv.removeChild(obj);
} catch(e){
return false; }
return ture; }
return false; }
var a = {
nodeType:1}
console.log(isElement(document.getElementById("test")));
console.log(isElement(document.getElementById("test").nextSibling));
console.log(isElement(a));
</script>