codemirror

What is codemirror?

CodeMirror is a versatile text editor implemented in JavaScript for the browser. It is specialized for editing code and comes with a number of language modes and addons that implement more advanced editing functionality. A rich programming API and a CSS theming system are available for customizing CodeMirror to fit the needs of the project.

What are codemirror's main functionalities?

Syntax highlighting

This feature allows for syntax highlighting of code written in various programming languages. The example code initializes a CodeMirror instance with JavaScript syntax highlighting.

var editor = CodeMirror.fromTextArea(document.getElementById('code'), {mode: 'javascript'});

Code editing

CodeMirror provides a rich text editor for code, with features like auto-indentation, line numbers, and bracket matching. The example code creates an editor instance with some JavaScript code pre-filled.

var editor = CodeMirror(document.body, {value: 'function myScript(){return 100;}', mode: 'javascript'});

Autocompletion

Autocompletion can be enabled to suggest completions for the current token. The example code sets up an event listener to trigger autocompletion on certain inputs.

editor.on('inputRead', function onChange(editor, input) { if (input.text[0] === ';' || input.text[0] === ' ') { return; } CodeMirror.commands.autocomplete(editor); });

Themes

CodeMirror supports various themes to customize the appearance of the editor. The example code initializes a CodeMirror instance with the Monokai theme.

var editor = CodeMirror.fromTextArea(document.getElementById('code'), {mode: 'javascript', theme: 'monokai'});

Addons

CodeMirror has a variety of addons that can extend its functionality, such as displaying line numbers or matching brackets. The example code enables line numbers and bracket matching for the editor.

var editor = CodeMirror.fromTextArea(document.getElementById('code'), {mode: 'javascript', lineNumbers: true, matchBrackets: true});

Other packages similar to codemirror

ace

Ace is a standalone code editor written in JavaScript. It matches many of the features of CodeMirror, such as syntax highlighting, themes, and extensions. However, Ace is known for its performance and is used in large-scale applications like Cloud9 IDE.

monaco-editor

Monaco Editor is the code editor that powers VS Code, which is known for its rich IntelliSense, integrated debugging, and embedded Git control. It's more feature-rich compared to CodeMirror and is designed to work well in any browser.

brace

Brace is a fork of Ace that is browserify compatible. It has a similar feature set to Ace and by extension, CodeMirror, but it is designed to be easier to install and use with browserify.

README

CodeMirror

CodeMirror is a versatile text editor implemented in JavaScript for the browser. It is specialized for editing code, and comes with over 100 language modes and various addons that implement more advanced editing functionality. Every language comes with fully-featured code and syntax highlighting to help with reading and editing complex code.

A rich programming API and a CSS theming system are available for customizing CodeMirror to fit your application, and extending it with new functionality.

You can find more information (and the manual) on the project page. For questions and discussion, use the discussion forum.

See CONTRIBUTING.md for contributing guidelines.

The CodeMirror community aims to be welcoming to everybody. We use the Contributor Covenant (1.1) as our code of conduct.

Installation

Either get the zip file with the latest version, or make sure you have Node installed and run:

npm install codemirror

NOTE: This is the source repository for the library, and not the distribution channel. Cloning it is not the recommended way to install the library, and will in fact not work unless you also run the build step.

Quickstart

To build the project, make sure you have Node.js installed (at least version 6) and then npm install. To run, just open index.html in your browser (you don't need to run a webserver). Run the tests with npm test.