Anp.UsbDeviceDescriptors 1.0.0

UsbDeviceDescriptors

Reads USB descriptors on Windows—Device, Configuration, Interface, Endpoint, and String—via the Win32 IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION control code, and exposes them as strongly‑typed C# structures. Targets .NET Framework 4.8, .NET Standard 2.0, .NET 8.0.

Features

• Strongly‑typed descriptors: DeviceDescriptor, ConfigurationDescriptor, InterfaceDescriptor, EndpointDescriptor, StringDescriptor, plus RawDescriptor for unknown blocks. All implement meaningful ToString() for inspection.
• One‑call read: UsbDescriptorReader.GetDescriptors(...) returns a hierarchical UsbDescriptorSet (device → configurations → interfaces → endpoints).
• Selectively include configurations and/or string descriptors with ReadOptions.
• Windows‑only; uses CreateFile/DeviceIoControl and the USB hub IOCTL.
• Synchronous I/O; no additional native dependencies.

Install NuGet

Quick start

using System;
using System.Linq;
using Anp.UsbDeviceDescriptors;

class Program
{
    static void Main()
    {
        // Inputs:
        string parentNodeId = @"USB\ROOT_HUB30\4&17AA0D8F&0"; // example (PnP Device Instance ID of a USB hub)
        uint portIndex = 3;                                     // 1-based port number on that hub

        // Read full tree (device + configurations + strings, default langId = 0x0409 English)
        UsbDescriptorSet set = UsbDescriptorReader.GetDescriptors(
            parentNodeId, portIndex, ReadOptions.All /*, langId: 0x0409*/);

        Console.WriteLine(set);

        Console.WriteLine($"VID:PID = 0x{set.DeviceDescriptor.IdVendor:X4}:0x{set.DeviceDescriptor.IdProduct:X4}");
        Console.WriteLine($"Product: {set.DeviceDescriptor.ProductName}");

        foreach (var ep in set.EndpointDescriptors)
        {
            Console.WriteLine($"EP 0x{ep.EndpointAddress:X2} ({ep.TransferType}), wMaxPacketSize={ep.MaxPacketSize}");
        }
    }
}

Language IDs & string descriptors

Some devices localize their strings.

• UsbDescriptorReader.GetSupportedLanguageIds(parentNodeId, portIndex) — returns supported LANGIDs (lazy enumerable). Devices with no strings often return an empty set. Strings may be unavailable in low‑power states.
• UsbDescriptorReader.GetStringDescriptor(parentNodeId, portIndex, stringIndex, langId) — reads a specific string descriptor. Index 0 is reserved for the LANGID table.

Auto‑select the first available language:

using System.Linq;
using Anp.UsbDeviceDescriptors;

ushort lang = UsbDescriptorReader.GetSupportedLanguageIds(parentNodeId, portIndex).FirstOrDefault(); // 0 if none
var set = UsbDescriptorReader.GetDescriptors(parentNodeId, portIndex, ReadOptions.All, lang);

Inputs: Parent ID and Port index

This library reads USB descriptors via Windows API that requires parent info:

• Parent ID — the parent node (USB hub) Device Instance ID. A parent node symbolic name (\??\…) or a full device interface path (\\?\…) is also accepted.
• Port index — the 1‑based port number (bus address) on the parent hub where the target device is connected.

Parent info is exposed by the Pnp Device Discovery library or can be obtained by other means.

API overview

Entry points

• UsbDescriptorReader.GetDescriptors(string parentNodeId, uint portIndex, ReadOptions options = ReadOptions.All, ushort langId = 0x0409)
• UsbDescriptorReader.GetSupportedLanguageIds(string parentNodeId, uint portIndex)
• UsbDescriptorReader.GetStringDescriptor(string parentNodeId, uint portIndex, byte stringIndex, ushort langId = 0x0409)

Options

[Flags]
public enum ReadOptions
{
    None = 0,
    Configurations = 1,
    Strings = 2,
    All = Configurations | Strings
}

Build & support

• Targets: .NET Framework 4.8, .NET Standard 2.0, .NET 8.0
• Language: C# 7.3
• Interop: Windows‑only (Win32 CreateFile/DeviceIoControl).

License

MIT — see LICENSE.