Possible Duplicate:
Javascript isDOM — How do you check if a Javascript Object is a DOM Object?
What is a safest technique for checking if an unknown variable is a native DOM element? Both of these seem to work:
// instanceof
function isElementInstance(ukn) {
return ukn instanceof Element;
}
// nodeType
function isElementNode(ukn) {
return 1 === ukn.nodeType;
}