How can I call method that has a delegate parameter using reflection?

Question

How can I call the method below using reflection?

namespace Awesomium.Core
{
    public delegate JSValue JavascriptMethodHandler(object sender, JavascriptMethodEventArgs e);

    public class JSObject
    {
        public void Bind(string methodName, JavascriptMethodHandler handler)
        {
            // Does something...
        }
    }
}

My progress is below. I get exception on CreateDelegate.

Cannot bind to the target method because its signature or security transparency is not compatible with that of the delegate type.

public class AwesomiumHelper
{
    private Func<object, dynamic, dynamic> JavascriptMethodHandlerAction;

    public void RegisterJavascriptMethodAndBind(string methodName, Func<object, dynamic, dynamic> func)
    {
        if (func != null)
        {
            var jsoType = AwesomiumCore.GetExportedTypes().First(f => f.Name == "JSObject");
            var jso = Activator.CreateInstance(jsoType);

            var t = AwesomiumCore.GetTypes().FirstOrDefault(f => f.Name == "JavascriptMethodHandler");

            var mi = typeof(AwesomiumHelper).GetMethod("JavascriptMethodHandlerProxy", BindingFlags.NonPublic | BindingFlags.Instance);

            // GETTING EXCEPTION HERE
            var d = Delegate.CreateDelegate(t, this, mi);
            // GETTING EXCEPTION HERE

            JavascriptMethodHandlerAction = func;

            var mi0 = jsoType.GetMethod("Bind", new[] { typeof(string), t });
            mi0.Invoke(jso, new object[] { methodName, d });
        }
    }

    private dynamic JavascriptMethodHandlerProxy(object sender, dynamic e)
    {
        return JavascriptMethodHandlerAction?.Invoke(sender, e);
    }
}

UPDATE: I solved the problem by creating two libraries. Interface library and class library. Interface library is referenced by the class library and main program. Awesomium is referenced by class library. At runtime I am loading class library by reflection and use its methods which are defined in interface library.

This is question is different because it has a delegate parameter. — Egemen Çiftci, Oct 07 '16 at 06:13
You're right, this is different enough. And i see no obvious duplicate. — H H, Oct 08 '16 at 13:48

score 0 · Answer 1 · answered Oct 10 '16 at 08:08

0

The problem is that you misunderstood the first argument of CreateDelegate - it refers to the type of the delegate, not the target:

var d = Delegate.CreateDelegate(typeof(Func<object, dynamic, dynamic>), this, mi);

answered Oct 10 '16 at 08:08

Luaan

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But type of the delegate that I want to reflect is JavascriptMethodHandler. – Egemen Çiftci Oct 10 '16 at 12:25
@Tempeck Well, it doesn't match the signature of the method, so you can't. If you really want to, you could use a wrapper function to "translate" the two, but be careful - `dynamic` is kind of infectious :) – Luaan Oct 10 '16 at 14:42

How can I call method that has a delegate parameter using reflection?

1 Answers1