tree-selector
v2.1.1
Published
Use CSS selectors to match nodes in a custom object tree
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tree-selector
build a matching or query function for CSS selectors for any nested object structure!
import { createQuerySelector, createMatches } from 'tree-selector';
const options = {
tag: n => n.tagName,
contents: n => n.innerText,
id: n => n.id,
class: n => n.className,
parent: n => n.parentElement,
children: n => n.childNodes,
attr: (n, attr) => n.getAttribute(attr)
};
const querySelector = createQuerySelector(options);
const matches = createMatches(options);
const selector = 'span.mySpan';
const element = document.getElementsByClassName('span')[0]
if(matches(selector, element)) {
// there are elements matching the selector
} else {
// no elements found
}
//Also possible, but less efficient
if(querySelector(selector, element).length > 0) {
// there are elements found
}
API
createQuerySelector(options) -> querySelector
Configure tree-selector
for the nested object structure you'll want to match against.
createMatches(options) -> matches
Configure a matches
function for a node in your tree structure. (This is used internally by createQuerySelector
)
options
options
are an object of lookup functions for queried nodes. You only need to provide the configuration necessary for the selectors you're planning on creating.
(If you're not going to use #id
lookups, there's no need to provide the id
lookup in your options.)
tag
: Extract tag information from a node fordiv
style selectors.contents
: Extract text information from a node, for:contains(xxx)
selectors.id
: Extract id for#my_sweet_id
selectors.class
:.class_name
parent
: Used for sibling selectorschildren
: Used to traverse from a parent to its children for sibling selectorsdiv + span
,a ~ p
.attr
: Used to extract attribute information, for[attr=thing]
style selectors.
Supported pseudoclasses
:first-child
:last-child
:nth-child
:empty
:root
:contains(text)
Supported attribute lookups
[attr=value]
: Exact match[attr]
: Attribute exists and is not false-y.[attr$=value]
: Attribute ends with value[attr^=value]
: Attribute starts with value[attr*=value]
: Attribute contains value[attr~=value]
: Attribute, split by whitespace, contains value.[attr|=value]
: Attribute, split by-
, contains value.