Utilities to select dom elements and handle events
npm install @drivy/dom-queryUtility functions to easily perform DOM element manipulation:
- Element selection based on css query selectors. Chainable. NodeLists automatically converted as Arrays
- Helpers to Attach/detach events. Event delegation supported
This library is provided as an ES module with Typescript declarations.
Install with npm:
``ts`
$ npm install @drivy/dom-query
Install with yarn:
`ts`
$ yarn add @drivy/dom-query
`ts
import { query, queryAll } from "@drivy/dom-query";
queryAll(".home-header").map(header => console.log(header));
// =>
query(".confirm-button").on("click", e => {
confirm(e.target);
});
`
query
- selects an element from the DOM with a css query selector.
- returns null if no element matches the selector.
- chainable. Chained method will be based on the last selected element context
queryStrict
- like query method but will raise en exception if no element matches the selector.
queryAll
- selects a list of elements from the DOM with a css query selector. NodeList results will be converted to Arrays so you can directly access Array methods (forEach, map, reduce, filter...)
Examples:
`ts
import { query, queryStrict, queryAll } from "@drivy/dom-query"
...
const myElement = query(".js_my-element")
const mySubElement = myElement.query(".js_my-sub-element")
const mySubElements = myElement.queryAll(".js_my-sub-elements")
queryAll(".js_my-container .js_my-children-to-select").map(enhancedElement => {
doSomething(enhancedElement)
})
const myElement2 = queryStrict(".js_my-existing-element")
//code below won't be reached if the previous element was not found
doSomething(myElement2)
`
You can transform an existing javascript Element/List of Elements to an EnhancedHTMLElement/EnhancedHTMLElementList with the following methods:
- toEnhancedHTMLElement
-
You have to use those methods when input elements are out of your scope (function args, event.target ...)
`ts
import { toEnhancedHTMLElement, toEnhancedHTMLElementList } from "@drivy/dom-query"
...
const myElement = toEnhancedHTMLElement(myHTMLElement);
const myElements = toEnhancedHTMLElementList(myHTMLElements);
`
You can attach/detach events with the following methods:
EnhancedHTMLElement.on
- attaches event like native target.addEventListener.target.removeEventListener
- returns a "detach" function. When called, will remove the event listener like .
EnhancedHTMLElementList.on
- same parameters and behavior than EnhancedHTMLElement.on but the event will be attached on each element contained in the list.
- returns a "detach" function that when called will detach the events attached on each element of the list
EnhancedHTMLElement.onDelegate
- does event delegation. pattern description here.
- like .on method but takes an extra parameter (first one) as a css query selector to specify the children to use as event targets
- returns a "detach" function. When called, will remove the event listener attached to the container.
EnhancedHTMLElementList.onDelegate
- same parameters and behavior than EnhancedHTMLElement.onDelegate but the event delegation will be done for each element of the list.
- returns a "detach" function that when called will detach the events attached on each element of the list
Examples:
`ts
// EnhancedHTMLElement
const detach = myElement.on("click", e => {
doSomething(e.target)
})
...
detach() //same behavior than native target.removeEventListener
const detachDelegation = myContainer.onDelegate(".js_sub-elements", "click", e => {
doSomething(e.target)
});
// clicking on a child having the "js_sub-elements" class will trigger the event
...
detachDelegation() // remove event listener used to delegate
// EnhancedHTMLElementList
const detach = queryAll(".js_my-elements").on("click", e => {
doSomething(e.target)
})
...
detach()
const detachDelegations = queryAll(".js_my-elements").onDelegate(
".js_my-sub-elements",
"click",
e => {
doSomething(e.target)
}
)
...
detachDelegations()
`
#### Event configuration
When attaching an event with .on or .onDelegate you can specify an optional event configuration object as last parameter.once
This configuration object has a boolean property that when true will automatically detach the event after having called once.
`ts`
myElement2.on(
"click",
e => {
doSomething(e.target);
// event listener will be detached
},
{
once: true
}
);
#### Specializing the HTMLElement (ex: HTMLInputElement)
Because EnhancedHTMLElement enhances HTMLElement by default, to access properties/methods from an enhanced HTMLInputElement with Typescript (ex: myEnhancedInput.value), you must declare the target Type when calling the query/converting method
`ts
import { query, queryAll, toEnhancedHTMLElement } from "@drivy/dom-query"
...
const myEnhancedInput = query
doSomething(myEnhancedInput.value)
const myEnhancedInput2 = toEnhancedHTMLElement
doSomething(myEnhancedInput2.value)
const myEnhancedInputs = queryAll
myEnhancedInputs.forEach(myInput => {
doSomething(myInput.value);
})
``