In this quickstart, you incorporate Azure Cache for Redis into a .NET Core app to have access to a secure, dedicated cache that is accessible from any application within Azure. You specifically use the StackExchange.Redis client with C# code in a .NET Core console app.

Clone the repo https://github.com/Azure-Samples/azure-cache-redis-samples/tree/main/quickstart/dotnet-core on GitHub.

• Azure subscription - create one for free
• .NET Core SDK

[!INCLUDE redis-cache-create]

[!INCLUDE redis-cache-access-keys]

Make a note of the HOST NAME and the Primary access key. You'll use these values later to construct the CacheConnection secret.

In your command window, execute the following command to store a new secret named CacheConnection, after replacing the placeholders (including angle brackets) for your cache name and primary access key:

dotnet user-secrets set CacheConnection "<cache name>.redis.cache.windows.net,abortConnect=false,ssl=true,allowAdmin=true,password=<primary-access-key>"

The connection to your cache is managed by the RedisConnection class. The connection is first made in this statement from Program.cs:

      _redisConnection = await RedisConnection.InitializeAsync(connectionString: configuration["CacheConnection"].ToString());

In RedisConnection.cs, you see the StackExchange.Redis namespace has been added to the code. This is needed for the RedisConnection class.

using StackExchange.Redis;

The RedisConnection code ensures that there is always a healthy connection to the cache by managing the ConnectionMultiplexer instance from StackExchange.Redis. The RedisConnection class recreates the connection when a connection is lost and unable to reconnect automatically.

For more information, see StackExchange.Redis and the code in a GitHub repo.

In program.cs, you can see the following code for the RunRedisCommandsAsync method in the Program class for the console application:

private static async Task RunRedisCommandsAsync(string prefix)
    {
        // Simple PING command
        Console.WriteLine($"{Environment.NewLine}{prefix}: Cache command: PING");
        RedisResult pingResult = await _redisConnection.BasicRetryAsync(async (db) => await db.ExecuteAsync("PING"));
        Console.WriteLine($"{prefix}: Cache response: {pingResult}");

        // Simple get and put of integral data types into the cache
        string key = "Message";
        string value = "Hello! The cache is working from a .NET console app!";

        Console.WriteLine($"{Environment.NewLine}{prefix}: Cache command: GET {key} via StringGetAsync()");
        RedisValue getMessageResult = await _redisConnection.BasicRetryAsync(async (db) => await db.StringGetAsync(key));
        Console.WriteLine($"{prefix}: Cache response: {getMessageResult}");

        Console.WriteLine($"{Environment.NewLine}{prefix}: Cache command: SET {key} \"{value}\" via StringSetAsync()");
        bool stringSetResult = await _redisConnection.BasicRetryAsync(async (db) => await db.StringSetAsync(key, value));
        Console.WriteLine($"{prefix}: Cache response: {stringSetResult}");

        Console.WriteLine($"{Environment.NewLine}{prefix}: Cache command: GET {key} via StringGetAsync()");
        getMessageResult = await _redisConnection.BasicRetryAsync(async (db) => await db.StringGetAsync(key));
        Console.WriteLine($"{prefix}: Cache response: {getMessageResult}");

        // Store serialized object to cache
        Employee e007 = new Employee("007", "Davide Columbo", 100);
        stringSetResult = await _redisConnection.BasicRetryAsync(async (db) => await db.StringSetAsync("e007", JsonSerializer.Serialize(e007)));
        Console.WriteLine($"{Environment.NewLine}{prefix}: Cache response from storing serialized Employee object: {stringSetResult}");

        // Retrieve serialized object from cache
        getMessageResult = await _redisConnection.BasicRetryAsync(async (db) => await db.StringGetAsync("e007"));
        Employee e007FromCache = JsonSerializer.Deserialize<Employee>(getMessageResult);
        Console.WriteLine($"{prefix}: Deserialized Employee .NET object:{Environment.NewLine}");
        Console.WriteLine($"{prefix}: Employee.Name : {e007FromCache.Name}");
        Console.WriteLine($"{prefix}: Employee.Id   : {e007FromCache.Id}");
        Console.WriteLine($"{prefix}: Employee.Age  : {e007FromCache.Age}{Environment.NewLine}");
    }

Cache items can be stored and retrieved by using the StringSetAsync and StringGetAsync methods.

In the example, you can see the Message key is set to value. The app updated that cached value. The app also executed the PING and command.

The Redis server stores most data as strings, but these strings can contain many types of data, including serialized binary data, which can be used when storing .NET objects in the cache.

Azure Cache for Redis can cache both .NET objects and primitive data types, but before a .NET object can be cached it must be serialized.

This .NET object serialization is the responsibility of the application developer, and gives the developer flexibility in the choice of the serializer.

The following Employee class was defined in Program.cs so that the sample could also show how to get and set a serialized object :

class Employee
    {
        public string Id { get; set; }
        public string Name { get; set; }
        public int Age { get; set; }

        public Employee(string id, string name, int age)
        {
            Id = id;
            Name = name;
            Age = age;
        }
    }

If you have opened any files, save them and build the app with the following command:

dotnet build

Run the app with the following command to test serialization of .NET objects:

dotnet run

:::image type="content" source="media/cache-dotnet-core-quickstart/cache-console-app-complete.png" alt-text="Console app completed":::

If you continue to use this quickstart, you can keep the resources you created and reuse them.

Otherwise, if you're finished with the quickstart sample application, you can delete the Azure resources created in this quickstart to avoid charges.

1. Sign in to the Azure portal and select Resource groups.

2. In the Filter by name... textbox, type the name of your resource group. The instructions for this article used a resource group named TestResources. On your resource group in the result list, select ... then Delete resource group.

   :::image type="content" source="media/cache-dotnet-core-quickstart/cache-delete-resource-group.png" alt-text="Delete":::

3. You'll be asked to confirm the deletion of the resource group. Type the name of your resource group to confirm, and select Delete.

After a few moments, the resource group and all of its contained resources are deleted.

• Connection resilience
• Best Practices Development