Can a DOM element have an ID that contains a space?

Question

And if so, how do you select on with jQuery? I.e., $(\"#a b\") looks for all nodes within the node with id=a.

Answer 1

While this is an old question I thought I would share info on the HTML 5 Spec for those who come across this question as I did a few years after it was asked.

According to the HTML 5 Spec:

The value must be unique amongst all the IDs in the element's home subtree and must contain at least one character. The value must not contain any space characters.

It also says:

There are no other restrictions on what form an ID can take; in particular, IDs can consist of just digits, start with a digit, start with an underscore, consist of just punctuation, etc.