Send and Receive Messages with .NET SDK

Architecture Overview

┌──────────────────┐                              ┌──────────────────┐
│  Sender Console  │                              │ Receiver Console │
│       App        │                              │       App        │
└────────┬─────────┘                              └────────┬─────────┘
         │                                                 │
         │  ServiceBusSender                ServiceBusReceiver
         │                                                 │
         ▼                                                 ▼
┌─────────────────────────────────────────────────────────────────────┐
│                    Azure Service Bus Namespace                       │
│  ┌───────────────────────────────────────────────────────────────┐  │
│  │                      orders-queue                              │  │
│  │  [Msg1] [Msg2] [Msg3] ──────────────────────────▶ [Consumer]  │  │
│  └───────────────────────────────────────────────────────────────┘  │
└─────────────────────────────────────────────────────────────────────┘

Prerequisites

Requirement	Details
.NET SDK	8.0+
Service Bus Namespace	From previous tutorial
Queue	`orders-queue` created
IDE	Visual Studio / VS Code / Rider

Step 1 — Create a Console Application

dotnet new console -n ServiceBusDemo
cd ServiceBusDemo

Step 2 — Install the NuGet Package

dotnet add package Azure.Messaging.ServiceBus

Step 3 — Send a Single Message

using Azure.Messaging.ServiceBus;

const string connectionString = "<YOUR_CONNECTION_STRING>";
const string queueName = "orders-queue";

await using var client = new ServiceBusClient(connectionString);
ServiceBusSender sender = client.CreateSender(queueName);

var message = new ServiceBusMessage("Hello, Service Bus!");
await sender.SendMessageAsync(message);

Console.WriteLine("Message sent successfully.");

Screenshot: Console output after sending message

Step 4 — Send a Batch of Messages

using Azure.Messaging.ServiceBus;

const string connectionString = "<YOUR_CONNECTION_STRING>";
const string queueName = "orders-queue";

await using var client = new ServiceBusClient(connectionString);
ServiceBusSender sender = client.CreateSender(queueName);

using ServiceBusMessageBatch batch = await sender.CreateMessageBatchAsync();

for (int i = 1; i <= 10; i++)
{
    var message = new ServiceBusMessage($"Order #{i}");
    if (!batch.TryAddMessage(message))
    {
        throw new Exception($"Message {i} too large for batch.");
    }
}

await sender.SendMessagesAsync(batch);
Console.WriteLine($"Sent batch of {batch.Count} messages.");

Step 5 — Receive Messages

using Azure.Messaging.ServiceBus;

const string connectionString = "<YOUR_CONNECTION_STRING>";
const string queueName = "orders-queue";

await using var client = new ServiceBusClient(connectionString);
ServiceBusReceiver receiver = client.CreateReceiver(queueName);

Console.WriteLine("Receiving messages...");

IReadOnlyList<ServiceBusReceivedMessage> messages =
    await receiver.ReceiveMessagesAsync(maxMessages: 10, maxWaitTime: TimeSpan.FromSeconds(5));

foreach (ServiceBusReceivedMessage msg in messages)
{
    Console.WriteLine($"Received: {msg.Body}");
    await receiver.CompleteMessageAsync(msg);
}

Console.WriteLine($"Processed {messages.Count} messages.");

Screenshot: Console output receiving messages

Step 6 — Complete vs Abandon Messages

Action	Method	Effect
Complete	`CompleteMessageAsync()`	Removes message from queue
Abandon	`AbandonMessageAsync()`	Returns message to queue, increments delivery count
Defer	`DeferMessageAsync()`	Moves to deferred state, receive by sequence number
Dead-letter	`DeadLetterMessageAsync()`	Moves to dead-letter sub-queue

foreach (ServiceBusReceivedMessage msg in messages)
{
    try
    {
        ProcessOrder(msg.Body.ToString());
        await receiver.CompleteMessageAsync(msg);
    }
    catch (Exception ex)
    {
        Console.WriteLine($"Error: {ex.Message}. Abandoning message.");
        await receiver.AbandonMessageAsync(msg);
    }
}

Step 7 — Connection String vs Managed Identity

Connection String (development)

await using var client = new ServiceBusClient(connectionString);

Managed Identity (production recommended)

dotnet add package Azure.Identity

using Azure.Identity;
using Azure.Messaging.ServiceBus;

const string fullyQualifiedNamespace = "sb-demo-namespace.servicebus.windows.net";

await using var client = new ServiceBusClient(
    fullyQualifiedNamespace,
    new DefaultAzureCredential());

Approach	Use Case	Security
Connection String	Local dev, quick tests	Shared secret — rotate regularly
Managed Identity	Production, Azure-hosted apps	No secrets to manage
Workload Identity	Kubernetes / AKS	Federated token exchange

Assign RBAC Role for Managed Identity

az role assignment create \
  --assignee <PRINCIPAL_ID> \
  --role "Azure Service Bus Data Sender" \
  --scope /subscriptions/<SUB_ID>/resourceGroups/rg-servicebus-demo/providers/Microsoft.ServiceBus/namespaces/sb-demo-namespace

Screenshot: RBAC role assignment in portal

Summary

✅ Created a .NET console app with the Service Bus SDK
✅ Sent single and batch messages
✅ Received and completed messages
✅ Understood Complete vs Abandon semantics
✅ Configured Managed Identity for production

Previous: Create a Service Bus Namespace and Queue

Next: Topics, Subscriptions, and Message Filtering