@bun-win32/comctl32

Zero-dependency, zero-overhead Win32 Comctl32 bindings for Bun on Windows.

Overview

@bun-win32/comctl32 exposes the comctl32.dll exports using Bun's FFI. It provides a single class, Comctl32, which lazily binds native symbols on first use. You can optionally preload a subset or all symbols up-front via Preload().

The bindings are strongly typed for a smooth DX in TypeScript.

Features

• Bun-first ergonomics on Windows 10/11.
• Direct FFI to comctl32.dll (common controls, image lists, property sheets, DPA/DSA dynamic arrays, flat scroll bars, window subclassing).
• In-source docs in structs/Comctl32.ts with links to Microsoft Docs.
• Lazy binding on first call; optional eager preload (Comctl32.Preload()).
• No wrapper overhead; calls map 1:1 to native APIs.
• Strongly-typed Win32 aliases (see types/Comctl32.ts).

Requirements

• Bun runtime
• Windows 10 or later

Installation

bun add @bun-win32/comctl32

Quick Start

import Comctl32, { DllVersionPlatform, ImageListCreateFlags } from '@bun-win32/comctl32';

Comctl32.Preload(['DllGetVersion', 'ImageList_Create', 'ImageList_Destroy', 'ImageList_GetImageCount', 'InitCommonControls']);

Comctl32.InitCommonControls();

const dllVersionInfoBuffer = Buffer.alloc(20);
dllVersionInfoBuffer.writeUInt32LE(20, 0);

if (Comctl32.DllGetVersion(dllVersionInfoBuffer.ptr) !== 0) {
  throw new Error('DllGetVersion failed');
}

const majorVersion = dllVersionInfoBuffer.readUInt32LE(4);
const minorVersion = dllVersionInfoBuffer.readUInt32LE(8);
const buildNumber = dllVersionInfoBuffer.readUInt32LE(12);
const platform = DllVersionPlatform[dllVersionInfoBuffer.readUInt32LE(16)];

console.log(`comctl32 v${majorVersion}.${minorVersion}.${buildNumber} (${platform})`);

const imageListHandle = Comctl32.ImageList_Create(16, 16, ImageListCreateFlags.ILC_COLOR32 | ImageListCreateFlags.ILC_MASK, 8, 4);

if (imageListHandle === 0n) {
  throw new Error('ImageList_Create failed');
}

console.log(`ImageList handle 0x${imageListHandle.toString(16)} — ${Comctl32.ImageList_GetImageCount(imageListHandle)} images`);

Comctl32.ImageList_Destroy(imageListHandle);

[!NOTE] AI agents: see AI.md for the package binding contract and source-navigation guidance. It explains how to use the package without scanning the entire implementation.

Examples

Run the included examples:

bun run example:common-controls-inspector
bun run example:dpa-sort-race

Notes

• Either rely on lazy binding or call Comctl32.Preload().
• Windows only. Bun runtime required.