using System;
using System.Runtime.InteropServices;
using System.Reflection;

namespace TestAcad {
    public class Program {
        
        public static void Main(String[] args) {
            Object acad = Marshal.GetActiveObject("AutoCAD.Application");
            setProperty(acad, "Visible", true);
            Object document = getProperty(acad, "ActiveDocument");
            Object model = getProperty(document, "ModelSpace");
            
            double[] a = { 0, 0, 0 }, b = { 100, 100, 0 };
            Object line = invoke(model, "AddLine", a, b);
            setProperty(line, "color", 1);
            
            Object utility = getProperty(document, "Utility");
            
            Object[] parameters = { new Object(), new Object(), "Укажите линию" };
            invoke(utility, "GetEntity", modifiers(true, true), parameters);
            
            setProperty(parameters[0], "color", 1);
        }
        
        
        private static Type invoker = new Object().GetType();

        public static Object getProperty(Object target, String name) {
            return invoker.InvokeMember(name, BindingFlags.GetProperty, null, target, null);
        }

        public static void setProperty(Object target, String name, params Object[] values) {
            invoker.InvokeMember(name, BindingFlags.SetProperty, null, target, values);
        }

        public static Object invoke(Object target, String name, params Object[] values) {
            return invoker.InvokeMember(name, BindingFlags.InvokeMethod, null, target, values);
        }

        public static Object invoke(Object target, String name, ParameterModifier[] mod, Object[] values) {
            return invoker.InvokeMember(name, BindingFlags.InvokeMethod, null, target, values, mod, null, null);
        }

        public static ParameterModifier[] modifiers(params bool[] values) {
            ParameterModifier[] parameterModifiers = new ParameterModifier[values.Length];
            for (int i = 0; i < values.Length; ++i) {
                parameterModifiers[i] = new ParameterModifier(1);
                parameterModifiers[i][0] = values[i];
            }
            return parameterModifiers;
        }
    }
}