Code blocks are a simple way to display formatted code with syntax highlighting.

Code blocks by default are a simple way to display code. But, BlockNote also supports more advanced features like:

• Syntax highlighting
• Custom themes
• Multiple languages
• Tab indentation

Configuration Options

type CodeBlockOptions = {
  indentLineWithTab?: boolean;
  defaultLanguage?: string;
  supportedLanguages?: Record<
    string,
    {
      name: string;
      aliases?: string[];
    }
  >;
  createHighlighter?: () => Promise<HighlighterGeneric<any, any>>;
};

indentLineWithTab: Whether the Tab key should indent lines, or not be handled by the code block specially. Defaults to true.

defaultLanguage: The syntax highlighting default language for code blocks which are created/inserted without a set language, which is text by default (no syntax highlighting).

supportedLanguages: The syntax highlighting languages supported by the code block, which is an empty array by default.

createHighlighter: The Shiki highliter to use for syntax highlighting.

BlockNote also provides a generic set of options for syntax highlighting in the @blocknote/code-block package, which support a wide range of languages:

import { createCodeBlockSpec } from "@blocknote/core";
import { codeBlockOptions } from "@blocknote/code-block";

const codeBlock = createCodeBlockSpec(codeBlockOptions);

See this example to see it in action.

Type & Props

type CodeBlock = {
  id: string;
  type: "codeBlock";
  props: {
    language: string;
  } & DefaultProps;
  content: InlineContent[];
  children: Block[];
};

language: The syntax highlighting language to use. Defaults to text, which has no highlighting.

To create your own syntax highlighter, you can use the shiki-codegen CLI for generating the code to create one for your chosen languages and themes.

For example, to create a syntax highlighter using the optimized javascript engine, javascript, typescript, vue, with light and dark themes, you can run the following command:

npx shiki-codegen --langs javascript,typescript,vue --themes light,dark --engine javascript --precompiled ./shiki.bundle.ts

This will generate a shiki.bundle.ts file that you can use to create a syntax highlighter for your editor.

Like this:

import { createHighlighter } from "./shiki.bundle.js";

export default function App() {
  const editor = useCreateBlockNote({
    schema: BlockNoteSchema.create().extend({
      codeBlock: createCodeBlockSpec({
        indentLineWithTab: true,
        defaultLanguage: "typescript",
        supportedLanguages: {
          typescript: {
            name: "TypeScript",
            aliases: ["ts"],
          },
        },
        createHighlighter: () =>
          createHighlighter({
            themes: ["light-plus", "dark-plus"],
            langs: [],
          }),
      }),
    }),
  });

  return <BlockNoteView editor={editor} />;
}

See the custom code block example for a more detailed example.