QuickMember 2.0.0

QuickMember

Fast by-name member access for .NET. Based on FastMember by Marc Gravell.

What is this?

In .NET, reflection is slow. If you need access to the members of an arbitrary type, with the type and member names known only at runtime, it is frankly hard (especially for DLR types). This library makes such access easy and fast by generating IL at runtime that approaches the speed of direct compiled property access.

Installation

dotnet add package QuickMember

Targets: netstandard2.0, net8.0, net10.0

Usage

Type-level access (best for many objects of the same type)

var accessor = TypeAccessor.Create(typeof(MyType));

while (/* some loop of data */)
{
    accessor[obj, "Name"] = rowValue;
}

Object-level access (wraps a single instance)

var wrapped = ObjectAccessor.Create(obj); // works with static and DLR types
Console.WriteLine(wrapped["Name"]);

As an IDataReader (for SqlBulkCopy, DataTable, TVPs)

Load a DataTable from a sequence of objects:

IEnumerable<Customer> data = GetCustomers();
var table = new DataTable();
using (var reader = ObjectReader.Create(data))
{
    table.Load(reader);
}

Bulk-insert into a database:

using var bcp = new SqlBulkCopy(connection);
using var reader = ObjectReader.Create(data, "Id", "Name", "Email");
bcp.DestinationTableName = "Customers";
bcp.WriteToServer(reader);

Non-public members

var accessor = TypeAccessor.Create(typeof(MyType), allowNonPublicAccessors: true);
accessor[obj, "InternalProp"] = value;

Member inspection

var accessor = TypeAccessor.Create(typeof(MyType));
var members = accessor.GetMembers();

foreach (var member in members)
{
    Console.WriteLine($"{member.Name}: {member.Type} (CanRead={member.CanRead}, IsIndexer={member.IsIndexer})");
}

Column ordering with OrdinalAttribute

public class Customer
{
    [Ordinal(2)]
    public string Email { get; set; }

    [Ordinal(0)]
    public int Id { get; set; }

    [Ordinal(1)]
    public string Name { get; set; }
}

Benchmarks

Accessor Performance (get + set per call)

BenchmarkDotNet v0.15.8, .NET 10.0.5, AMD Ryzen 9 7950X

| Method                   |       Mean | Allocated |
|------------------------- |-----------:|----------:|
| Static C# (baseline)     |   0.163 ns |       0 B |
| Dynamic C#               |   4.379 ns |       0 B |
| TypeAccessor             |   9.983 ns |       0 B |
| ObjectAccessor           |  10.533 ns |       0 B |
| PropertyInfo             |  14.073 ns |       0 B |
| PropertyDescriptor       |  47.308 ns |      32 B |
| TypeAccessor.CreateNew   |   3.392 ns |      24 B |
| Activator.CreateInstance |   8.742 ns |      24 B |

Construction & Memory

| Method                       |        Mean | Allocated |
|----------------------------- |------------:|----------:|
| GetMembers (cached)          |    0.608 ns |       0 B |
| ObjectAccessor.Create        |   12.110 ns |     120 B |
| ObjectReader.Create (8 cols) |  348.893 ns |   1,000 B |
| ObjectReader.Read+GetValues  |  292.711 ns |   1,240 B |
| GetSchemaTable               | 2,608.989 ns|  11,832 B |

Changes from FastMember

QuickMember is a derivative work of FastMember (Apache-2.0). Key changes:

Features

• Member.IsIndexer -- detect indexer properties to avoid exceptions when iterating all members
• Non-public property discovery -- TypeAccessor.Create(type, allowNonPublicAccessors: true) now finds internal/private properties (not just non-public getters/setters on public properties)
• IsKey column in GetSchemaTable -- enables ObjectReader as a table-valued parameter source for SqlParameter

Ahead of Time

This library emits IL at runtime. It will not work in constrained AOT environments (iOS, Unity IL2CPP, NativeAOT without rd.xml configuration).

License

Apache-2.0. See LICENSE and NOTICE for original attribution.