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Reflection

Reflection lets you inspect and use type information at runtime — discovering the type of an object, listing its members, reading attributes, or invoking methods by name. TinyCLR's reflection API lives in the standard System.Reflection namespace and mirrors the desktop .NET surface (minus a few advanced features).

Common embedded uses: looking up a handler method by string name, parsing custom attributes for configuration metadata, or serializing arbitrary objects to JSON.

Getting an object's type​

var i = 20;
Type type = i.GetType();
// type.FullName == "System.Int32"

Invoking a private method by name​

Reflection can reach into members that aren't publicly accessible — useful for testing, plugin patterns, or working around third-party APIs that didn't expose what you need.

Given a class with two private methods:

public class ReflectionExample {
    private uint FunctionA() => 0x1234;
    private uint FunctionB(uint numPlus) => 0x1234 + numPlus;
}

You can look up and invoke each by name:

using System;
using System.Diagnostics;
using System.Reflection;

var r = new ReflectionExample();
var type = r.GetType();

// No-argument private method.
var methodA = type.GetMethod("FunctionA", BindingFlags.NonPublic | BindingFlags.Instance);
var valueA = methodA.Invoke(r, null);

// Private method taking one argument.
var methodB = type.GetMethod("FunctionB", BindingFlags.NonPublic | BindingFlags.Instance);
var valueB = methodB.Invoke(r, new object[] { (uint)1 });

Debug.WriteLine("methodA: " + valueA);      // 4660  (= 0x1234)
Debug.WriteLine("methodB: " + valueB);      // 4661  (= 0x1234 + 1)

The BindingFlags.NonPublic | BindingFlags.Instance combination is required to find private instance methods — without NonPublic, only public members are matched; without Instance, only static members are matched.

tip

Reflection isn't free. Looking up members by string name is slower than direct invocation, and Invoke boxes value-type arguments and return values. For performance-sensitive code paths, cache the MethodInfo you get from GetMethod and reuse it rather than looking it up every call.