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CSharp · Console

/Program.cs

using System;
using System.Reflection;
using System.Reflection.Emit;

public class Program
{
	public static void Main(string[] args)
	{
        var method = GetDM();
        var result = method.Invoke(null, new Object[]{"Test 1234", true});
		Console.WriteLine(result); // Should be 2
	}
    
    public static int Test(Object[] args)
    {
		Console.WriteLine(args.Length);
		return args.Length;
    }
        
    public static DynamicMethod GetDM() {  
        var returnType = typeof(int);
        var paramTypes = new Type[]{typeof(string), typeof(bool)};
        
        var method = new DynamicMethod(
            "",
            returnType,
            paramTypes,
            false
        );
        var il = method.GetILGenerator();
        
        // Save parameters in an object array
        il.Emit(OpCodes.Ldc_I4_S, paramTypes.Length);
		il.Emit(OpCodes.Newarr, typeof(Object));
		il.Emit(OpCodes.Dup);
		
		for (int i = 0; i < paramTypes.Length; i++)
		{
			Type type = paramTypes[i];
			
			il.Emit(OpCodes.Ldc_I4, i);
			il.Emit(OpCodes.Ldarg, i);
			if (type.IsValueType) { il.Emit(OpCodes.Box, type); }
			il.Emit(OpCodes.Stelem_Ref);
			il.Emit(OpCodes.Dup);
		}
		
        // Call method and get the length of the array
        // How do I return the result of the called method?
        var callMethod = typeof(Program).GetMethod("Test", (BindingFlags)(-1));
        il.Emit(OpCodes.Call, callMethod);
        
        il.Emit(OpCodes.Ret);
        
        return method;
    }
}