KnockoutJs v2.3.0 : Error You cannot apply bindings multiple times to the same element

Question

I\'ve just upgraded to 2.3.0 and now I\'m getting the error

You cannot apply bindings multiple times to the same element.

that

Answer 1

Something that can happen as well which throws this exception is the following. Say you have:

ko.applyBindings(myViewModel1, document.getElementById('element1'));
...
ko.applyBindings(myViewModel2, document.getElementById('element2'));

Now, when both #element1 and #element2 don't exist you'll get the error. The reason is that Knockout's applyBindings falls back on document.body as root element when #element1 and #element2 are not found. Now it tries to apply binding twice on the body...

Not a nice fallback of Knockout if you ask me. I'd rather have a clear error message that the element does not exist in the DOM (yet).

Hope this helps some people.