Tips for verifying whether a variable is a node?

Curiosity strikes me: how can I determine if the variable myVar is a node?

I could simply check myVar.nodeType, but that might be misleading with something like {nodeType:1}

So, naturally, I start to wonder if there's a way to do this instead:

myVar instanceof Node

Edit

Interesting discovery - it seems that we have a Node constructor, so using instanceof Node actually does work!

Maybe I should have tested my theory before asking...

Let's not mistake my question for a duplicate of Check if variable is a valid node element. Unlike that question, mine doesn't make any assumptions about whether myVar is a node or empty.

javascriptnodestypecheckingdom-node

Answer №1

Experiment with window.document instanceof Node across various web browsers. It shows as true in IE11, GC30, FF24, and Opera17, indicating compatibility with other Nodes as well.

In more outdated browsers such as IE8, the Node interface appears as undefined. While testing interfaces like HTMLDivElement for div nodes, it proved to be too specific, necessitating a cumbersome logical expression using ||. The most versatile interface functioning in IE8 is Element: both window.document.body and its child nodes are recognized as instances of Element. An interesting point to note is that whilst window.document is not an Element, it is actually an HTMLDocument.

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