Anp.Usb.Hid.Win32 1.0.0

Anp.Usb.Hid.Win32

Managed Windows HID library for .NET Framework 4.8, .NET Standard 2.0, and .NET 8+. Focused on basic I/O for custom communication devices that use the "driverless" HID transport — not aimed at system HID devices (keyboards, mice, gamepads). Provides device discovery, hot-plug monitoring, and async I/O via Win32 P/Invoke.

Devices can be created from the built-in discovery or from an externally obtained device interface path (e.g. a config file, a saved preference, or a tool like PnpDeviceToolkit).

Features

• Discovery — enumerate HID devices, optionally filtered by USB VID/PID
• Hot-plug monitoring — get notified when devices arrive or are removed (Windows 8+)
• Async I/O — ReadInputReportAsync, WriteOutputReportAsync, ReadInputDataAsync, WriteOutputDataAsync with meaningful per-call timeouts
• Sync wrappers — ReadInputReport, WriteOutputReport, WriteOutputData for simple use cases
• Feature reports — ReadFeatureReport, WriteFeatureReport (synchronous HID class driver calls)
• Raw data and report access — work with HidReport (report ID + payload) or raw byte arrays; read exact byte counts across multiple reports via ReadInputDataAsync
• Graceful disconnect handling — mid-I/O device removal throws HidDisconnectedException, leaving the device in a clean closed state
• Device metadata — ProductName, SerialNumber, VendorId, ProductId, VersionNumber, Usage, UsagePage, report lengths — all probed at construction
• Extensible — subclass HidDevice with OnOpened() / OnClosing() hooks for protocol initialization and teardown; use GetDevices<T> for typed discovery
• Diagnostics — subscribe to HidDiag.Error for library-level error reporting

Quick Start

Discover devices

using Anp.Usb.Hid.Win32;

// All HID devices
var devices = HidDiscovery.GetDevices();

// Filter by USB VID/PID
var filtered = HidDiscovery.GetDevices(vendorId: 0x04D8, productId: 0x003F);

foreach (var device in devices)
{
    Console.WriteLine($"{device.ProductName} (VID={device.VendorId}, PID={device.ProductId}, Usage=0x{device.Usage:X2}, Page=0x{device.UsagePage:X4})");
    device.Dispose();
}

Open, write, read

using Anp.Usb.Hid.Win32;

// From discovery, config file, or any external source
var device = new HidDevice(@"\\?\HID#VID_04D8&PID_003F#...");
device.Open();

// Write an output report
var report = new HidReport(0x00, new byte[] { 0x01, 0x02, 0x03 });
await device.WriteOutputReportAsync(report);

// Read an input report
HidReport input = await device.ReadInputReportAsync(timeout: TimeSpan.FromSeconds(5));
Console.WriteLine($"Report ID: {input.ReportId}, Data: {BitConverter.ToString(input.Data)}");

device.Close();
device.Dispose();

Write and read raw data (no report framing)

// Write raw bytes — automatically framed into an output report
await device.WriteOutputDataAsync(new byte[] { 0x01, 0x02, 0x03 }, reportId: 0x00);

// Read exactly N bytes of input data (loops across multiple reports)
byte[] data = await device.ReadInputDataAsync(bytesToRead: 64);

Feature reports

// Write a feature report
var feature = new HidReport(0x01, new byte[] { 0xAA, 0xBB });
device.WriteFeatureReport(feature);

// Read a feature report
HidReport result = device.ReadFeatureReport(reportId: 0x01);

Monitor hot-plug events

using Anp.Usb.Hid.Win32;

using (var watcher = new HidWatcher(vendorId: 0x04D8))
{
    watcher.DeviceArrived += (s, e) => Console.WriteLine($"Connected: {e.DevicePath}");
    watcher.DeviceRemoved += (s, e) => Console.WriteLine($"Disconnected: {e.DevicePath}");
    watcher.StartWatching();

    Console.ReadLine(); // keep alive
}

Subclass for protocol initialization

public class MyHidDevice : HidDevice
{
    public MyHidDevice(string path) : base(path) { }

    protected override void OnOpened()
    {
        // Device is open — send initialization command, etc.
        WriteOutputDataAsync(new byte[] { 0x01 }).GetAwaiter().GetResult();
    }

    protected override void OnClosing()
    {
        // Device is about to close — send shutdown command, etc.
        WriteOutputDataAsync(new byte[] { 0xFF }).GetAwaiter().GetResult();
    }
}

// Use with discovery
var devices = HidDiscovery.GetDevices<MyHidDevice>(path => new MyHidDevice(path));

API Overview

HidDevice

All async methods accept an optional TimeSpan? timeout parameter (default: 2 seconds).

HidReport

HidDiscovery

HidWatcher

Diagnostics

HidDiag.Error += (sender, error) =>
{
    Console.WriteLine($"[{error.Member}] {error.Message} {error.Exception}");
};

Requirements

• .NET Framework 4.8, .NET Standard 2.0, or .NET 8+ (Windows)
• Windows Vista or later (discovery and I/O)
• Windows 8 or later (HidWatcher hot-plug monitoring)

License

See LICENSE in the repository root.

Links

• GitHub
• NuGet