Is it possible to set this static private member of a static class with reflection?

Question

I have a static class with static private readonly member that\'s set via the class\'s static constructor. Below is a simplified example.

Answer 1

Here is a quick example showing how to do it:

using System;
using System.Reflection;

class Example
{
    static void Main()
    {
        var field = typeof(Foo).GetField("bar", 
                            BindingFlags.Static | 
                            BindingFlags.NonPublic);

        // Normally the first argument to "SetValue" is the instance
        // of the type but since we are mutating a static field we pass "null"
        field.SetValue(null, "baz");
    }
}

static class Foo
{
    static readonly String bar = "bar";
}

Answer 2

This "null rule" also applies to FieldInfo.GetValue() for a static field, e.g.,

Console.Writeline((string)(field.GetValue(null)));