如何使用方法名称获取非静态MethodInfo（不在字符串中，不在类类型中搜索）

Question

Consider following code:

public class Test
{
    [System.AttributeUsage(System.AttributeTargets.Method)]
    class MethodAttribute : System.Attribute
    {
        public MethodAttribute(System.Reflection.MethodInfo methodInfo)
        {

        }
    }

    public void Foo()
    {

    }

    [Method(Test.Foo)] //< THIS IS THE IMPORTANT LINE
    public void Boo()
    {

    }
}

I want to store MethodInfo instance of Foo in attribute of Boo, but problem is, that I cannot use Foo nor Test.Foo to get instance of MethodInfo . I can NOT use typeof(Test).GetMethod("Foo") (not my decision).

Important information:

• Generated error is: error CS0120: An object reference is required to access non-static member `Test.Foo()'
• I'm coding in Unity3D which is using Mono, not .Net. (more info http://docs.unity3d.com/410/Documentation/ScriptReference/MonoCompatibility.html )
• Windows 7

Absolutely unimportant information:

• Why I cannot use typeof(Test).GetMethod("Foo") : I'm not allowed. It's not in my power to change this decision. I can not . (Also, personally, I would like to avoid it anyway as it needs to do some lookup instead of getting statically the data. Also it won't be changed automatically during refactoring and will be checking run-time, not compile-time.)
• Why I want to do this: later in code, I want to create a delegate of Boo() (this time normally, with an instance) and use in special even system or something. Before it's called, this attribute allows to setup method to be called in prepare for main event (it's optional, it can be null) and I know how to create a delegate when I have an object and a method info.
• Why I cannot just provide both delegates when registering or something: because class containing these methods is not always the one who registers to event source, I need to keep the registration code as simple as possible. In other words, I want to avoid situation when person writing method responsible for connecting forgots to add this preparation delegate.

Answer 1

use expression :

static public class Metadata<T>
{
    static public PropertyInfo Property<TProperty>(Expression<Func<T, TProperty>> property)
    {
        var expression = property.Body as MemberExpression;
        return expression.Member as PropertyInfo;
    }
}

var foo = Metadata<Test>.Property(test => test.Foo);