up.fragment up.fragment.etag(element)

JavaScript function

Returns the ETag of the content in the given element.

The returned ETag corresponds to the ETag header in the response that rendered the fragment. Alternatively the [up-etag] attribute of the element or an ancestor is used.

If no ancestor fragment with an [up-etag] attribute exists, undefined is returned.

When the fragment is reloaded, its ETag is sent as an If-None-Match request header. The server may check the header and decide to skip rendering.