public static MethodDelegate CreateMethod()

in src/Serialization/ReflectionExtentions.cs [70:122]
51 lines of code
7 McCabe index (conditional complexity)

        public static MethodDelegate CreateMethod(this MethodInfo methodInfo, bool isStatic)
        {
            var parameters = methodInfo.GetParameters();
            string delegateName;
            Type[] genericTypes;
            if (parameters.Length == 0)
            {
                if (methodInfo.ReturnType == typeof(void))
                {
                    delegateName = "CreateMethodDelegate0";
                    genericTypes = new[] { methodInfo.DeclaringType };
                }
                else
                {
                    delegateName = "CreateMethodDelegate1";
                    genericTypes = new[] { methodInfo.DeclaringType, methodInfo.ReturnType };
                }
            }
            else if (parameters.Length == 1)
            {
                if (methodInfo.ReturnType == typeof(void))
                {
                    delegateName = "CreateMethodDelegate3";
                    genericTypes = new[] { methodInfo.DeclaringType, parameters[0].ParameterType };
                }
                else
                {
                    delegateName = "CreateMethodDelegate4";
                    genericTypes = new[] { methodInfo.DeclaringType, parameters[0].ParameterType, methodInfo.ReturnType };
                }
            }
            else if (parameters.Length == 2)
            {
                // e.g. Dictionary.Add(key, value)
                if (methodInfo.ReturnType == typeof(void))
                {
                    delegateName = "CreateMethodDelegate5";
                    genericTypes = new[] { methodInfo.DeclaringType, parameters[0].ParameterType, parameters[1].ParameterType };
                }
                else
                {
                    throw new NotSupportedException($"{methodInfo.Name}: 2 parameters with return type.");
                }
            }
            else
            {
                throw new NotSupportedException($"{methodInfo.Name}: more than 2 parameters.");
            }

            MethodInfo m1 = typeof(ReflectionExtentions).GetMethod(delegateName, BindingFlags.Static | BindingFlags.NonPublic);
            MethodInfo m2 = m1.MakeGenericMethod(genericTypes);
            return (MethodDelegate)m2.Invoke(null, new object[] { methodInfo });
        }