Print HTML elements in modern browsers.
npm install printd> Print HTML elements or pages in modern browsers. :printer:
Printd opens your Browser Print Dialog to print HTML elements inside a blank document or pages by URL.
- Written and tested entirely in Typescript.
- Tiny script (around 1KB gzipped with no dependencies).
- Print any element _without_ opening a new window.
- Print only when assets such as images or fonts are ready (loaded).
- Print pages by URL.
- Add styles and scripts on demand using text or URL.
- š Live Demo
- š Simple Code Example - Clone this repository and just run npm run sample
- š Vue Code example
``sh`
yarn add printd
`sh`
npm install printd --save
UMD file is also available on unpkg:
`html`
You can use the library via window.printd.
`ts
import { Printd } from 'printd'
const cssText =
h1 {
color: black;
font-family: sans-serif;
}
const d = new Printd()
d.print( document.getElementById('myelement'), [ cssText ] )
`
- __parent__: Optional parent element where the printable element will be appended. Default window.document.body
- __headElements__: Optional custom document elements array.body
- __bodyElements__: Optional custom document elements array.
Example:
`ts
// custom base element example
const base = document.createElement('base')
base.setAttribute('href', 'https://your-cdn.dev')
// define options to use
const options = {
parent: document.getElementById('myparent'),
headElements: [ base ]
}
const d = new Printd(options)
`
Function to print an HTMLElement.
`ts`
d.print (element, styles, scripts, callback)
__Print parameters:__
- __element:__ Some HTMLElement object to print.document.head
- __styles:__ Optional styles (array of texts or urls) that will add to iframe ()document.body
- __scripts:__ Optional scripts (array of texts or urls) that will add to iframe ()HTMLIFrameElement
- __callback:__ Optional callback that will be triggered when content is ready to print.
- __callback arguments:__
- __iframe__: An reference. It already contains contentWindow and contentDocument references.HTMLElement
- __element__: An copy (cloned node) reference of current element to print.
- __launchPrint__: Function to launch the print dialog after assets (images, fonts, etc) was loaded.
#### 1. Basic example
`ts
const d = new Printd()
d.print( document.getElementById('h1'), [h1 { font-family: serif; }] )`
#### 2. Callback example
Callback option is suitable when you plan to print elements or pages with assets (images, fonts, etc) but you need to wait for them. Your callback will be triggered only when your assets are loaded.
`ts
const d = new Printd()
// Tip: texts & urls are supported
const styles = [
'https://your-cdn.dev/style.css',
.code { font-family: monospace; }
]
const scripts = [
'https://your-cdn.dev/script.js',
(() => console.log('Hello from IFrame!'))()
]
// Get an HTMLElement reference
const el = document.getElementById('mycode-block')
// Trigger the print dialog on demand
const printCallback = ({ launchPrint }) => launchPrint()
d.print(el, styles, scripts, printCallback)
`
Function to print an URL.
__PrintURL parameters:__
- __url:__ URL to print.
- __callback:__ Optional callback that will be triggered when content is ready to print.
`ts
const d = new Printd()
d.printURL('http://127.0.0.1/', ({ launchPrint }) => {
console.log('Content loaded!')
// fire printing!
launchPrint()
})
`
Printd provides convenient print event methods on top of the Browser beforeprint and afterprint events.print()
However note that they only work when printing custom HTML elements via the method.
`ts
const d = new Printd()
d.onBeforePrint((event) => console.log(event, "called before printing!"))
d.onAfterPrint((event) => console.log(event, "called after printing!"))
d.print(document.getElementById('myelement'))
`
Gets the current HTMLIFrameElement reference.
Examples:
`ts
const d = new Printd()
const iframe = d.getIFrame()
// a) Subscribe to IFrame load event
iframe.addEventListener('load', () => console.log('iframe loaded!'))
// b) Subscribe to Window beforeprint or afterprint events`
const { contentWindow } = iframe
contentWindow.addEventListener('beforeprint', () => console.log('before print!'))
contentWindow.addEventListener('afterprint', () => console.log('after print!'))
- Chrome Desktop 63+
- Chrome for Android 63+
- Firefox 6+
- Edge
- Internet Explorer 11
- Opera Desktop 50+
- Opera for Android 50+
__References:__
- Chrome Platform Status - beforeprint and afterprint events
- https://caniuse.com/#feat=beforeafterprint
- PR: Update support for before/after print event handlers (Blink)
- https://developer.mozilla.org/en-US/docs/Web/API/WindowEventHandlers/onbeforeprint
For Webkit-based browsers, it can create an equivalent result using window.matchMedia('print').
`ts
if (contentWindow.matchMedia) {
const mediaQueryList = contentWindow.matchMedia('print')
mediaQueryList.addListener((mql) => {
if (mql.matches) {
console.log('before print!')
} else {
console.log('after print!')
}
})
}
``
__References:__
- https://developer.mozilla.org/en-US/docs/Web/API/WindowEventHandlers/onbeforeprint
- https://www.tjvantoll.com/2012/06/15/detecting-print-requests-with-javascript/
Since Printd uses an underlying iframe it's highly recommended to ensure that only your content will be displayed.
As a fallback you could remove the hidden iframe after some printing.
Here some interesting security advices that you want to take at look:
- Why are iframes considered dangerous and a security risk?
- MDN: X-Frame-Options
- Play safely in sandboxed IFrames
Feel free to send some Pull request or issue.
Ā© 2017-present Jose Quintana