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

According to the HTML 4.0 specification for basic types:

ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").

And even if spaces were valid, an id attribute with spaces would be interpreted by jQuery as an ancestor descendant selector with the current selector syntax.