ckeditor5-code-block

pre element (to write longer code snippets) for CKEditor 5. https://ckeditor.com

this will enable add code block feature to editor with language select, edit, highlight feature. languages are added that supported by Javascript syntax highlighter. Additionally edit option is provided where we can edit language name. actually it adds entered language as classname to pre element.

Example

There are CKEditor5 Builds available on there official page as

Classic editor, Inline editor, Balloon editor, Document editor

let assume Classic editor example

First, install the build from npm:

npm install --save @ckeditor/ckeditor5-build-classic

And use it in your website:

<div id="editor">
	<p>This is the editor content.</p>
</div>
<script src="./node_modules/@ckeditor/ckeditor5-build-classic/build/ckeditor.js"></script>
<script>
	ClassicEditor
		.create( document.querySelector( '#editor' ) )
		.then( editor => {
			window.editor = editor;
		} )
		.catch( err => {
			console.error( err.stack );
		} );
</script>

Or in your JavaScript application:

import ClassicEditor from '@ckeditor/ckeditor5-build-classic';

// Or using the CommonJS version:
// const ClassicEditor = require( '@ckeditor/ckeditor5-build-classic' );

ClassicEditor
	.create( document.querySelector( '#editor' ) )
	.then( editor => {
		window.editor = editor;
	} )
	.catch( err => {
		console.error( err.stack );
	} );

Note: If you are planning to integrate CKEditor 5 deep into your application, it is actually more convenient and recommended to install and import the source modules directly (like it happens in ckeditor.js). Read more in the Advanced setup guide.

Including ckeditor5-code-block with classic editor

now install code-block package

npm install ckeditor5-code-block

open "ckeditor5-build-classic/src/ckeditor.js" source file where you can see imported packages. now import ckeditor5-code-block as shown in below example and build.

// The editor creator to use.
import ClassicEditorBase from '@ckeditor/ckeditor5-editor-classic/src/classiceditor';

import Essentials from '@ckeditor/ckeditor5-essentials/src/essentials';
import UploadAdapter from '@ckeditor/ckeditor5-adapter-ckfinder/src/uploadadapter';
import Autoformat from '@ckeditor/ckeditor5-autoformat/src/autoformat';
import Bold from '@ckeditor/ckeditor5-basic-styles/src/bold';
import Italic from '@ckeditor/ckeditor5-basic-styles/src/italic';
import BlockQuote from '@ckeditor/ckeditor5-block-quote/src/blockquote';
import EasyImage from '@ckeditor/ckeditor5-easy-image/src/easyimage';
import Heading from '@ckeditor/ckeditor5-heading/src/heading';
import Image from '@ckeditor/ckeditor5-image/src/image';
import ImageCaption from '@ckeditor/ckeditor5-image/src/imagecaption';
import ImageStyle from '@ckeditor/ckeditor5-image/src/imagestyle';
import ImageToolbar from '@ckeditor/ckeditor5-image/src/imagetoolbar';
import ImageUpload from '@ckeditor/ckeditor5-image/src/imageupload';
import Link from '@ckeditor/ckeditor5-link/src/link';
import List from '@ckeditor/ckeditor5-list/src/list';
import Paragraph from '@ckeditor/ckeditor5-paragraph/src/paragraph';

import PreElement from 'ckeditor5-code-block/src/pre';
import PreElementToolbar from 'ckeditor5-code-block/src/preelementtoolbar'; // pre element toolbar to edit its language class

export default class ClassicEditor extends ClassicEditorBase {}

// Plugins to include in the build.
ClassicEditor.builtinPlugins = [
	Essentials,
	UploadAdapter,
	Autoformat,
	Bold,
	Italic,
	BlockQuote,
	EasyImage,
	Heading,
	Image,
	ImageCaption,
	ImageStyle,
	ImageToolbar,
	ImageUpload,
	Link,
	PreElement,
  PreElementToolbar,
	List,
	Paragraph
];

// Editor configuration.
ClassicEditor.defaultConfig = {
	toolbar: {
		items: [
			'heading',
			'|',
			'bold',
			'italic',
			'link',
			'bulletedList',
			'numberedList',
			'imageUpload',
      			'pre',
			'blockQuote',
			'undo',
			'redo'
		]
	},
	image: {
		toolbar: [
			'imageStyle:full',
			'imageStyle:side',
			'|',
			'imageTextAlternative'
		]
	},
	// This value must be kept in sync with the language defined in webpack.config.js.
	language: 'en'
};

After build you can see code block pre element icon in classic editor top bars.

Custom Options

you can define language select/edit or code remove option for code block. just add this options in editor config as shown in below example. custom tab in code edit added as no of white spaces. you can adjust this from same config option as below.

import ClassicEditor from '@ckeditor/ckeditor5-build-classic';
const hljs = require('./highlight.js');
// Or using the CommonJS version:
// const ClassicEditor = require( '@ckeditor/ckeditor5-build-classic' );

var _code_languages = ["plain","c","cs","cpp","html","xml","css","javascript","python","sql","php","perl","ruby","markdown","auto"];

ClassicEditor
	.create( document.querySelector( '#editor' ), {

	preCodeBlock :{

		languages: _code_languages.map( _language => {return{
			language: _language,
			title: _language=="cs"?"c#":_language
		};}),
		toolbar: [ 'EditLanguage', '|', 'SelectLanguage' , '|', 'HighlightCodeBlock', '|', 'CloseCodeBlock'],
			noOfSpaceForTabKey: 4,
		highlightConfig:{
			// this function is called whenever syntax highlighting is requested.
			// the highlighting pre element and language will be the arguments for this function
			// this function should return syntax highlighted block.
			// below example uses highlightjs as syntax highlighter
			highlighter:( pre_block, language )=>{

				// to undo highlighting simply uncomment below two lines and return pre_block as is
				// or you can select plain/text/nohighlight option from language if highlighter supports
				pre_block.innerHTML = pre_block.innerHTML.replace(/<br[ \/]*>/gi, '\n');
				hljs.highlightBlock(pre_block); // refer https://github.com/highlightjs/highlight.js
				return pre_block; // return highlighted pre block to plugin
			}
		}
	}

	} )
	.then( editor => {
		window.editor = editor;
	} )
	.catch( err => {
		console.error( err.stack );
	} );

Highlighter

Option of syntax highlighting is added for test purpose you can use/ignore it. this option will get active if we define highlighter function in highlightConfig and specify 'HighlightCodeBlock' option in toolbar while initializing the editor as shown in above example.

Above example uses the hljs syntax highlighter to hilight code. for more refer https://github.com/highlightjs/highlight.js

To highlight syntax select language from dropdown and click on highlight code block button in balloon option it will highlight the syntax as per highlighter defined in config.

To undo syntax highlighted block to plain text you can return same pre block without highlighting it or you can select plain/text/nohighlight language ( if your highlighter supports and added in your language options ) and click the highlight code block button.

key pairs added ctrl+uparrow and ctrl+downarrow to get outside when inside of codeblock.

Help to imporove this as i am new to this platform.

Thank you.

Licensed under the terms of GNU General Public License Version 2 or later. For full details about the license, please check the LICENSE.md file.