Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/react-simple-code-editor/react-simple-code-editor

Simple no-frills code editor with syntax highlighting
https://github.com/react-simple-code-editor/react-simple-code-editor

editor hacktoberfest react

Last synced: 30 days ago
JSON representation

Simple no-frills code editor with syntax highlighting

Awesome Lists containing this project

README 

        
# react-simple-code-editor



[![Build Status][build-badge]][build]

[![MIT License][license-badge]][license]

[![Version][version-badge]][package]

[![Bundle size (minified + gzip)][bundle-size-badge]][bundle-size]



Simple no-frills code editor with syntax highlighting.






## Why



Several browser based code editors such as Ace, CodeMirror, Monaco etc. provide the ability to embed a full-featured code editor in your web page. However, if you just need a simple editor with syntax highlighting without any of the extra features, they can be overkill as they don't usually have a small bundle size footprint. This library aims to provide a simple code editor with syntax highlighting support without any of the extra features, perfect for simple embeds and forms where users can submit code.



## Features



- Modular syntax highlighting with third party library

- Indent line or selected text by pressing tab key, with customizable indentation

- Automatic indent on new lines

- Wrap selected text in parens, brackets, or quotes

- Undo whole words instead of letter by letter

- Accessible, use `Ctrl+Shift+M` (Mac) / `Ctrl+M` to toggle capturing tab key



## Installation



```sh

npm install react-simple-code-editor

```



or



```sh

yarn add react-simple-code-editor

```



## Usage



You need to use the editor with a third party library which provides syntax highlighting. For example, it'll look like following with [`prismjs`](https://prismjs.com):



```js

import React from 'react';

import Editor from 'react-simple-code-editor';

import { highlight, languages } from 'prismjs/components/prism-core';

import 'prismjs/components/prism-clike';

import 'prismjs/components/prism-javascript';

import 'prismjs/themes/prism.css'; //Example style, you can use another



function App() {

  const [code, setCode] = React.useState(

    `function add(a, b) {\n  return a + b;\n}`

  );

  return (

     setCode(code)}

      highlight={code => highlight(code, languages.js)}

      padding={10}

      style={{

        fontFamily: '"Fira code", "Fira Mono", monospace',

        fontSize: 12,

      }}

    />

  );

}

```



Note that depending on your syntax highlighter, you might have to include additional CSS for syntax highlighting to work.



## Props



The editor accepts all the props accepted by `textarea`. In addition, you can pass the following props:



- `value` (`string`): Current value of the editor i.e. the code to display. This must be a [controlled prop](https://reactjs.org/docs/forms.html#controlled-components).

- `onValueChange` (`string => mixed`): Callback which is called when the value of the editor changes. You'll need to update the value prop when this is called.

- `highlight` (`string => string | React.Node`): Callback which will receive text to highlight. You'll need to return an HTML string or a React element with syntax highlighting using a library such as [`prismjs`](https://prismjs.com).

- `tabSize` (`number`): The number of characters to insert when pressing tab key. For example, for 4 space indentation, `tabSize` will be `4` and `insertSpaces` will be `true`. Default: `2`.

- `insertSpaces` (`boolean`): Whether to use spaces for indentation. Default: `true`. If you set it to `false`, you might also want to set `tabSize` to `1`.

- `ignoreTabKey` (`boolean`): Whether the editor should ignore tab key presses so that keyboard users can tab past the editor. Users can toggle this behaviour using `Ctrl+Shift+M` (Mac) / `Ctrl+M` manually when this is `false`. Default: `false`.

- `padding` (`number`): Optional padding for code. Default: `0`.

- `textareaId` (`string`): An ID for the underlying `textarea`, can be useful for setting a `label`.

- `textareaClassName` (`string`): A className for the underlying `textarea`, can be useful for more precise control of its styles.

- `preClassName` (`string`): A className for the underlying `pre`, can be useful for more precise control of its styles.



## Demo



[react-simple-code-editor.github.io/react-simple-code-editor](https://react-simple-code-editor.github.io/react-simple-code-editor/)



## How it works



It works by overlaying a syntax highlighted `
` block over a ``. When you type, select, copy text etc., you interact with the underlying ``, so the experience feels native. This is a very simple approach compared to other editors which re-implement the behaviour.



The syntax highlighting can be done by any third party library as long as it returns HTML and is fully controllable by the user.



The vanilla `` doesn't support inserting tab characters for indentation, so we re-implement it by listening to `keydown` events and programmatically updating the text. One caveat with programmatically updating the text is that we lose the undo stack, so we need to maintain our own undo stack. As a result, we can also implement improved undo behaviour such as undoing whole words similar to editors like VSCode.



## Limitations



Due to the way it works, it has certain limitations:



- The syntax highlighted code cannot have different font family, font weight, font style, line height etc. for its content. Since the editor works by aligning the highlighted code over a ``, changing anything that affects the layout can misalign it.

- The custom undo stack is incompatible with undo/redo items browser's context menu. However, other full featured editors don't support browser's undo/redo menu items either.

- The editor is not optimized for performance and large documents can affect the typing speed.

- We hide text in the textarea using `-webkit-text-fill-color: transparent`, which works in all modern browsers (even non-webkit ones such as Firefox and Edge). On IE 10+, we use `color: transparent` which doesn't hide the cursor. Text may appear bolder in unsupported browsers.



## Contributing



While developing, you can run the example app to test your changes:



```sh

yarn example

```



Make sure your code passes TypeScript and ESLint. Run the following to verify:



```sh

yarn typescript

yarn lint

```



To fix formatting errors, run the following:



```sh

yarn lint -- --fix

```



[build-badge]: https://img.shields.io/circleci/project/github/react-simple-code-editor/react-simple-code-editor/main.svg?style=flat-square

[build]: https://circleci.com/gh/react-simple-code-editor/react-simple-code-editor

[license-badge]: https://img.shields.io/npm/l/react-simple-code-editor.svg?style=flat-square

[license]: https://opensource.org/licenses/MIT

[version-badge]: https://img.shields.io/npm/v/react-simple-code-editor.svg?style=flat-square

[package]: https://www.npmjs.com/package/react-simple-code-editor

[bundle-size-badge]: https://img.shields.io/bundlephobia/minzip/react-simple-code-editor.svg?style=flat-square

[bundle-size]: https://bundlephobia.com/result?p=react-simple-code-editor