Dictionary extensions

The MADE.Collections.DictionaryExtensions class provides two commonly needed operations for Dictionary<TKey, TValue> that the standard library doesn't include.

AddOrUpdate

Adds a key-value pair to the dictionary if the key doesn't exist, or updates the value if it does. This replaces the pattern of checking ContainsKey before deciding whether to add or update:

using MADE.Collections;

var settings = new Dictionary<string, string>();

// Adds the key
settings.AddOrUpdate("Theme", "Dark");

// Updates the existing key
settings.AddOrUpdate("Theme", "Light");

This is useful for caching scenarios, configuration builders, or any situation where you're accumulating key-value pairs and duplicates should overwrite rather than throw.

GetValueOrDefault

Gets a value from the dictionary by key, or returns a specified default if the key doesn't exist:

using MADE.Collections;

var config = new Dictionary<string, string>
{
    ["DatabaseTimeout"] = "30",
};

var timeout = config.GetValueOrDefault("DatabaseTimeout", "60"); // "30"
var retries = config.GetValueOrDefault("MaxRetries", "3");       // "3" (default)

Note: .NET 8+ includes CollectionExtensions.GetValueOrDefault in the base class library. If you're targeting net8.0 or later exclusively, you can use the built-in version. The MADE extension remains available for compatibility and for scenarios where you want a non-null default value.