# Basic code block

> Code block with header, filename, language and copy button.

A shadcn/ui block from the [@reui](https://reui.io) registry, listed on [shadcn.exchange](https://shadcn.exchange/r/reui/c-code-block-1).

- Page, with a live preview: https://shadcn.exchange/r/reui/c-code-block-1
- Screenshot: https://abzjhwgwpdpz7ua5.public.blob.vercel-storage.com/shots/reui/c-code-block-1-light-2ea5c7ccb18a41d1.png
- Registry item: https://reui.io/r/new-york-v4/c-code-block-1.json
- Listed: 2026-10-13, source last changed 2026-10-13

## Install

```bash
npx shadcn@latest add https://reui.io/r/new-york-v4/c-code-block-1.json
```

Run it in a project that has shadcn/ui set up. It adds the files below and installs what they depend on.

## Dependencies

- Registry items: `@reui/code-block`

## Files

### `c-code-block-1.tsx`

```tsx
import {
  CodeBlock,
  CodeBlockCopyButton,
  CodeBlockHeader,
  CodeBlockLanguage,
  CodeBlockTitle,
} from "@/components/reui/code-block/code-block"

const code = `export function useTotals(items: Item[]) {
  return useMemo(() => {
    const subtotal = items.reduce((sum, item) => sum + item.price, 0)
    const tax = Math.round(subtotal * 0.2)
    return { subtotal, tax, total: subtotal + tax }
  }, [items])
}`

export function Pattern() {
  return (
    <div className="w-full max-w-2xl">
      <CodeBlock code={code} language="typescript" showLineNumbers>
        <CodeBlockHeader>
          <CodeBlockTitle>use-totals.ts</CodeBlockTitle>
          <CodeBlockLanguage />
          <CodeBlockCopyButton className="ml-auto" />
        </CodeBlockHeader>
      </CodeBlock>
    </div>
  )
}
```