예제 #1
0
        /// <summary>
        /// Saves the ref arguments of a given method using the
        /// <paramref name="arguments"/> from the <paramref name="invocationInfo"/>
        /// object.
        /// </summary>
        /// <param name="IL">The <see cref="CilWorker"/> that will emit the method body.</param>
        /// <param name="parameters">The parameters of the target method.</param>
        /// <param name="invocationInfo">The local variable that contains the <see cref="IInvocationInfo"/> instance.</param>
        /// <param name="arguments">The local variable that will store the arguments from the <see cref="IInvocationInfo"/> instance.</param>
        private static void SaveRefArguments(CilWorker IL, IEnumerable<ParameterDefinition> parameters,
            VariableDefinition invocationInfo, VariableDefinition arguments)
        {
            var body = IL.GetBody();
            var targetMethod = body.Method;
            var declaringType = targetMethod.DeclaringType;
            var module = declaringType.Module;

            // Save the arguments returned from the handler method
            var getArguments = module.ImportMethod<IInvocationInfo>("get_Arguments");

            IL.Emit(OpCodes.Ldloc, invocationInfo);
            IL.Emit(OpCodes.Callvirt, getArguments);
            IL.Emit(OpCodes.Stloc, arguments);

            var index = 0;
            foreach (var param in parameters)
            {
                if (!param.IsByRef())
                {
                    index++;
                    continue;
                }
                // Load the destination address
                IL.Emit(OpCodes.Ldarg, index + 1);

                // Load the argument value
                IL.Emit(OpCodes.Ldloc, arguments);
                IL.Emit(OpCodes.Ldc_I4, index++);
                IL.Emit(OpCodes.Ldelem_Ref);

                // Determine the actual parameter type
                var referenceType = param.ParameterType as ReferenceType;
                if (referenceType == null)
                    continue;

                var actualParameterType = referenceType.ElementType;
                IL.Emit(OpCodes.Unbox_Any, actualParameterType);
                IL.Stind(param.ParameterType);
            }
        }