Question

have found fragments to be very useful in constructing dynamic html – like using a bag of html elements and the bag itself dissolving when put into place – very nice.

I had assumed the methods for html elements and fragments were the same, but I think this is incorrect.

it seems that fragments have node methods – appendChild() etc – but do not have more sophisticated html element methods, for example, getElementsByTagName().

is this assessment correct? or am I shooting myself in the foot in a new way?

Answer 1

A DocumentFragment extends the Node interface and is defined as,

interface DocumentFragment : Node {
};

An HTMLElement extends from Element, and its interface is defined as,

interface HTMLElement : Element {
    attribute DOMString id;
    attribute DOMString title;
    attribute DOMString lang;
    attribute DOMString dir;
    attribute DOMString className;
};

Element in-turn extends the Node interface. It contains the method getElementsByTagName among several others,

interface Element : Node {
    ...
    NodeList getElementsByTagName(in DOMString name);
    ..
};

So to answer your question in short, a document fragment and an html element both share the node interface.