public void ListTopicSubscriptions()
        {
            // Snippet: ListTopicSubscriptions(string,string,int?,CallSettings)
            // Create client
            PublisherClient publisherClient = PublisherClient.Create();
            // Initialize request argument(s)
            string formattedTopic = PublisherClient.FormatTopicName("[PROJECT]", "[TOPIC]");
            // Make the request
            IPagedEnumerable <ListTopicSubscriptionsResponse, string> response =
                publisherClient.ListTopicSubscriptions(formattedTopic);

            // Iterate over all response items, lazily performing RPCs as required
            foreach (string item in response)
            {
                // Do something with each item
                Console.WriteLine(item);
            }

            // Or iterate over fixed-sized pages, lazily performing RPCs as required
            int pageSize = 10;

            foreach (FixedSizePage <string> page in response.AsPages().WithFixedSize(pageSize))
            {
                // Do something with each page of items
                Console.WriteLine("A page of results:");
                foreach (string item in page)
                {
                    Console.WriteLine(item);
                }
            }
            // End snippet
        }
        public void ListTopicSubscriptions_RequestObject()
        {
            // Snippet: ListTopicSubscriptions(ListTopicSubscriptionsRequest,CallSettings)
            // Create client
            PublisherClient publisherClient = PublisherClient.Create();
            // Initialize request argument(s)
            ListTopicSubscriptionsRequest request = new ListTopicSubscriptionsRequest
            {
                TopicAsTopicName = new TopicName("[PROJECT]", "[TOPIC]"),
            };
            // Make the request
            PagedEnumerable <ListTopicSubscriptionsResponse, SubscriptionName> response =
                publisherClient.ListTopicSubscriptions(request);

            // Iterate over all response items, lazily performing RPCs as required
            foreach (SubscriptionName item in response)
            {
                // Do something with each item
                Console.WriteLine(item);
            }

            // Or iterate over pages (of server-defined size), performing one RPC per page
            foreach (ListTopicSubscriptionsResponse page in response.AsRawResponses())
            {
                // Do something with each page of items
                Console.WriteLine("A page of results:");
                foreach (SubscriptionName item in page)
                {
                    Console.WriteLine(item);
                }
            }

            // Or retrieve a single page of known size (unless it's the final page), performing as many RPCs as required
            int pageSize = 10;
            Page <SubscriptionName> singlePage = response.ReadPage(pageSize);

            // Do something with the page of items
            Console.WriteLine($"A page of {pageSize} results (unless it's the final page):");
            foreach (SubscriptionName item in singlePage)
            {
                Console.WriteLine(item);
            }
            // Store the pageToken, for when the next page is required.
            string nextPageToken = singlePage.NextPageToken;
            // End snippet
        }