Even more DotNet stuff, help

GlitchyEngineHelper/DotNetScriptingHelper/InteropHelper.cs

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+using System.Diagnostics;
+using System.Reflection;
+using System.Runtime.InteropServices;
+
+namespace DotNetScriptingHelper;
+
+public class InteropHelper
+{
+    struct CreateArgs
+    {
+        public IntPtr Ptr;
+        public int Length;
+
+        public string ManagedCopy => Marshal.PtrToStringUTF8(Ptr, Length);
+    }
+
+    //[UnmanagedCallersOnly]
+    public static int SomeMethod(IntPtr args, int argLength)
+    {
+        Debug.WriteLine(typeof(InteropHelper).AssemblyQualifiedName);
+
+        return 5;
+    }
+
+    [UnmanagedCallersOnly]
+    public static IntPtr CreateInstance(IntPtr args, int argLength)
+    {
+        try
+        {
+            Debug.Assert(Marshal.SizeOf<CreateArgs>() == argLength, "Provided argument has wrong size.");
+            
+            CreateArgs createArgs = Marshal.PtrToStructure<CreateArgs>(args);
+            
+            string str = createArgs.ManagedCopy;
+            
+            Console.WriteLine($"Trying to get type \"{str}\"");
+            
+            Type? type = Type.GetType(createArgs.ManagedCopy, true);
+            
+            if (type == null)
+            {
+                Console.WriteLine("Type was null.");
+                return IntPtr.Zero;
+            }
+
+            object? instance = Activator.CreateInstance(type);
+
+            if (instance == null)
+                return IntPtr.Zero;
+
+            GCHandle handle = GCHandle.Alloc(instance);
+
+            return GCHandle.ToIntPtr(handle);
+        }
+        catch (Exception e)
+        {
+            Console.WriteLine(e);
+            throw;
+        }
+    }
+
+    [UnmanagedCallersOnly]
+    public static void CallMethod(IntPtr instance, IntPtr methodName, int methodNameLength)
+    {
+        GCHandle handle = GCHandle.FromIntPtr(instance);
+
+        if (handle.Target == null)
+            throw new Exception("Handle has no target?");
+
+        Type type = handle.Target.GetType();
+
+        string name = Marshal.PtrToStringUTF8(methodName, methodNameLength);
+
+        MethodInfo? mi = type.GetMethod(name);
+
+        if (mi == null)
+            throw new Exception("MethodInfo is null.");
+
+        mi.Invoke(handle.Target, null);
+    }
+
+
+    public delegate void FreeInstanceEntryPoint(IntPtr instance);
+
+    [UnmanagedCallersOnly]
+    public static void FreeInstance(IntPtr instance)
+    {
+        GCHandle handle = GCHandle.FromIntPtr(instance);
+        handle.Free();
+    }
+}