Strategy Design Pattern in C#: Complete Guide with Examples

The Strategy design pattern is a behavioral pattern that enables you to define a family of algorithms, encapsulate each one, and make them interchangeable. This pattern lets the algorithm vary independently from the clients that use it, providing a powerful way to handle multiple ways of performing the same task. In C#, the Strategy design pattern in C# is particularly valuable when you need to select an algorithm at runtime or when you want to avoid conditional statements that choose between different behaviors.

Understanding the Strategy design pattern in C# is essential for C# developers working with design patterns. It's one of the most commonly used behavioral patterns and provides a clean solution for managing algorithm variations. The Strategy design pattern in C# promotes the Open/Closed Principle by allowing you to extend functionality (add new strategies) without modifying existing code, and it supports the Single Responsibility Principle by separating algorithm implementation from the context that uses it.

When learning design patterns in C#, the Strategy pattern is often one of the first behavioral patterns developers encounter. It's particularly useful in C# applications because it works seamlessly with interfaces, dependency injection, and modern .NET features. Understanding how to implement the Strategy design pattern in C# helps you write more flexible, maintainable code that follows SOLID principles. If you're new to design patterns, check out The Big List of Design Patterns - Everything You Need to Know for an overview of all design pattern categories.

What is the Strategy Design Pattern in C#?

The Strategy design pattern in C# defines a family of algorithms, encapsulates each algorithm, and makes them interchangeable. The pattern allows the algorithm to vary independently from the clients that use it. Instead of implementing multiple versions of an algorithm directly in a class, the Strategy design pattern in C# delegates algorithm selection to separate strategy objects.

Core Concept

At its heart, the Strategy design pattern in C# solves a fundamental problem: how do you handle multiple ways of performing the same operation without creating complex conditional logic? Instead of using large if-else or switch statements to choose between different algorithms, you encapsulate each algorithm in its own class and make them interchangeable through a common interface.

This approach provides several key benefits when implementing the Strategy design pattern in C#:

• Flexibility: You can switch algorithms at runtime without modifying the client code
• Separation of Concerns: Algorithm implementation is separated from the context that uses it
• Open/Closed Principle: Easy to add new strategies without modifying existing code
• Testability: Each strategy can be tested independently
• Elimination of Conditionals: Replaces complex conditional logic with polymorphism

Pattern Structure

The Strategy design pattern in C# consists of three main components:

1. Strategy Interface: Defines the contract that all concrete strategies must follow
2. Concrete Strategies: Separate classes that implement different algorithm variations
3. Context: Maintains a reference to a Strategy object and delegates execution to it

Let's examine a basic implementation of the Strategy design pattern in C#:

// Strategy interface
public interface IPaymentStrategy
{
    void ProcessPayment(decimal amount);
}

// Concrete Strategies
public class CreditCardPayment : IPaymentStrategy
{
    public void ProcessPayment(decimal amount)
    {
        Console.WriteLine($"Processing ${amount} payment via Credit Card");
        // Credit card processing logic
    }
}

public class PayPalPayment : IPaymentStrategy
{
    public void ProcessPayment(decimal amount)
    {
        Console.WriteLine($"Processing ${amount} payment via PayPal");
        // PayPal processing logic
    }
}

public class BankTransferPayment : IPaymentStrategy
{
    public void ProcessPayment(decimal amount)
    {
        Console.WriteLine($"Processing ${amount} payment via Bank Transfer");
        // Bank transfer processing logic
    }
}

// Context class
public class PaymentProcessor
{
    private IPaymentStrategy _paymentStrategy;

    public PaymentProcessor(IPaymentStrategy paymentStrategy)
    {
        _paymentStrategy = paymentStrategy;
    }

    public void SetPaymentStrategy(IPaymentStrategy paymentStrategy)
    {
        _paymentStrategy = paymentStrategy;
    }

    public void ExecutePayment(decimal amount)
    {
        _paymentStrategy.ProcessPayment(amount);
    }
}

In this example of the Strategy design pattern in C#, IPaymentStrategy is the Strategy interface, CreditCardPayment, PayPalPayment, and BankTransferPayment are Concrete Strategies, and PaymentProcessor is the Context that uses the strategies.

When to Use Strategy Pattern

The Strategy design pattern in C# is ideal when you have multiple ways of performing the same operation and you want to be able to switch between them dynamically. Understanding when to apply the Strategy design pattern in C# helps prevent over-engineering while ensuring you leverage its benefits effectively.

The Strategy design pattern in C# is ideal when:

• You have multiple algorithms for performing the same task and want to choose one at runtime
• You want to avoid conditional statements that select between different behaviors
• You need to add new algorithms frequently without modifying existing code
• Algorithm implementation should be separated from the context that uses it
• You want to make algorithms interchangeable and testable independently

Common Use Cases

The Strategy design pattern in C# appears in many real-world scenarios where algorithm selection needs to vary. Here are some common use cases where this pattern provides significant value:

Payment Processing: Different payment methods (credit card, PayPal, bank transfer) can be implemented as separate strategies. The payment processor context can switch between payment strategies without changing its core logic. This is particularly useful in e-commerce applications where payment options may vary by region or customer preference. When implementing payment processing with the Strategy design pattern in C#, you create flexible systems that can easily accommodate new payment methods. This approach is similar to how creational patterns like the Factory Method Pattern handle object creation flexibility.

Sorting Algorithms: Different sorting strategies (quicksort, mergesort, heapsort) can be encapsulated as strategies. The sorting context can select the appropriate algorithm based on data size, data type, or performance requirements. This allows optimization without modifying the sorting interface. The Strategy design pattern in C# makes it easy to swap sorting algorithms based on runtime conditions.

Data Validation: Multiple validation rules can be implemented as strategies. A form validator can apply different validation strategies based on the type of data being validated or the context of the validation. This makes it easy to add new validation rules without modifying existing code. Using the Strategy design pattern in C# for validation provides flexibility while maintaining clean separation of concerns.

Compression Algorithms: Different compression algorithms (ZIP, RAR, 7Z) can be implemented as strategies. A file compression utility can select the appropriate compression strategy based on file type, size, or user preference. This provides flexibility while maintaining a consistent interface. The Strategy design pattern in C# enables runtime selection of compression methods.

Discount Calculation: E-commerce systems often need different discount calculation strategies (percentage, fixed amount, buy-one-get-one, seasonal). The pricing context can switch between discount strategies based on promotion type or customer tier. This makes it easy to add new discount types without modifying the pricing logic. Implementing discount calculations with the Strategy design pattern in C# creates maintainable pricing systems.

Strategy Pattern Implementation in C#

Let's explore a more comprehensive C# example that demonstrates the Strategy design pattern in C# in a real-world scenario: a shipping cost calculator for an e-commerce system.

// Strategy interface
public interface IShippingStrategy
{
    decimal CalculateShippingCost(decimal orderTotal, decimal weight);
    string GetShippingMethodName();
}

// Concrete Strategies
public class StandardShippingStrategy : IShippingStrategy
{
    public decimal CalculateShippingCost(decimal orderTotal, decimal weight)
    {
        // Standard shipping: $5 base + $0.50 per pound
        return 5.00m + (weight * 0.50m);
    }

    public string GetShippingMethodName()
    {
        return "Standard Shipping";
    }
}

public class ExpressShippingStrategy : IShippingStrategy
{
    public decimal CalculateShippingCost(decimal orderTotal, decimal weight)
    {
        // Express shipping: $15 base + $1.00 per pound
        return 15.00m + (weight * 1.00m);
    }

    public string GetShippingMethodName()
    {
        return "Express Shipping";
    }
}

public class FreeShippingStrategy : IShippingStrategy
{
    private readonly decimal _freeShippingThreshold;

    public FreeShippingStrategy(decimal freeShippingThreshold = 50.00m)
    {
        _freeShippingThreshold = freeShippingThreshold;
    }

    public decimal CalculateShippingCost(decimal orderTotal, decimal weight)
    {
        // Free shipping if order total exceeds threshold
        if (orderTotal >= _freeShippingThreshold)
        {
            return 0.00m;
        }
        
        // Otherwise, use standard shipping calculation
        return 5.00m + (weight * 0.50m);
    }

    public string GetShippingMethodName()
    {
        return "Free Shipping (if eligible)";
    }
}

// Context class
public class ShippingCalculator
{
    private IShippingStrategy _shippingStrategy;

    public ShippingCalculator(IShippingStrategy shippingStrategy)
    {
        _shippingStrategy = shippingStrategy;
    }

    public void SetShippingStrategy(IShippingStrategy shippingStrategy)
    {
        _shippingStrategy = shippingStrategy;
    }

    public ShippingQuote CalculateQuote(decimal orderTotal, decimal weight)
    {
        var cost = _shippingStrategy.CalculateShippingCost(orderTotal, weight);
        var method = _shippingStrategy.GetShippingMethodName();

        return new ShippingQuote
        {
            ShippingCost = cost,
            ShippingMethod = method,
            OrderTotal = orderTotal,
            Weight = weight,
            TotalCost = orderTotal + cost
        };
    }
}

// Supporting class
public class ShippingQuote
{
    public decimal ShippingCost { get; set; }
    public string ShippingMethod { get; set; }
    public decimal OrderTotal { get; set; }
    public decimal Weight { get; set; }
    public decimal TotalCost { get; set; }
}

This example demonstrates how the Strategy design pattern in C# allows the ShippingCalculator context to use different shipping cost calculation algorithms without modifying its core logic. Each strategy encapsulates its own calculation logic, making it easy to add new shipping methods or modify existing ones when implementing the Strategy design pattern in C#.

Strategy Pattern with Dependency Injection

In modern C# applications, the Strategy design pattern in C# works exceptionally well with dependency injection. This approach makes strategies more testable and follows SOLID principles more closely.

// Strategy interface
public interface IDiscountStrategy
{
    decimal CalculateDiscount(decimal originalPrice);
    string GetDiscountType();
}

// Concrete Strategies
public class PercentageDiscountStrategy : IDiscountStrategy
{
    private readonly decimal _percentage;

    public PercentageDiscountStrategy(decimal percentage)
    {
        _percentage = percentage;
    }

    public decimal CalculateDiscount(decimal originalPrice)
    {
        return originalPrice * (_percentage / 100m);
    }

    public string GetDiscountType()
    {
        return $"{_percentage}% Discount";
    }
}

public class FixedAmountDiscountStrategy : IDiscountStrategy
{
    private readonly decimal _fixedAmount;

    public FixedAmountDiscountStrategy(decimal fixedAmount)
    {
        _fixedAmount = fixedAmount;
    }

    public decimal CalculateDiscount(decimal originalPrice)
    {
        return Math.Min(_fixedAmount, originalPrice); // Don't discount more than the price
    }

    public string GetDiscountType()
    {
        return $"${_fixedAmount} Fixed Discount";
    }
}

// Context using dependency injection
public class PriceCalculator
{
    private readonly IDiscountStrategy _discountStrategy;

    public PriceCalculator(IDiscountStrategy discountStrategy)
    {
        _discountStrategy = discountStrategy ?? throw new ArgumentNullException(nameof(discountStrategy));
    }

    public PriceResult CalculateFinalPrice(decimal originalPrice)
    {
        var discount = _discountStrategy.CalculateDiscount(originalPrice);
        var finalPrice = originalPrice - discount;

        return new PriceResult
        {
            OriginalPrice = originalPrice,
            DiscountAmount = discount,
            DiscountType = _discountStrategy.GetDiscountType(),
            FinalPrice = finalPrice
        };
    }
}

// Supporting class
public class PriceResult
{
    public decimal OriginalPrice { get; set; }
    public decimal DiscountAmount { get; set; }
    public string DiscountType { get; set; }
    public decimal FinalPrice { get; set; }
}

When using dependency injection frameworks, you can register strategies and inject them into your context classes. This makes your code more testable and maintainable, following the same principles used in other design patterns. The Strategy design pattern in C# works exceptionally well with modern dependency injection frameworks, allowing you to manage strategy lifecycles and configuration through your DI container. Understanding dependency injection principles helps you leverage the Strategy design pattern in C# more effectively in your applications.

Understanding how the Strategy design pattern in C# relates to other design patterns helps you create more sophisticated and maintainable designs. The Strategy pattern is part of the behavioral design pattern family, alongside patterns like the State pattern and Template Method pattern, each serving different purposes in C# application design. When learning design patterns in C#, understanding these relationships helps you choose the right pattern for each situation. For example, creational patterns like the Builder Pattern handle object construction, while the Strategy design pattern in C# handles algorithm selection.

Strategy Pattern vs. Other Patterns

The Strategy design pattern in C# is often confused with other design patterns. Understanding the differences helps you choose the right pattern for your situation.

Strategy vs. State Pattern

The Strategy design pattern in C# is frequently confused with the State pattern because both use similar structures. However, they serve different purposes:

• Strategy Pattern: Algorithms are chosen externally (by the client). Strategies are independent and don't know about each other. The context doesn't change its behavior based on internal state.
• State Pattern: States are part of an object's lifecycle. States know about other states and can transition between them. The object's behavior changes based on its internal state.

The Strategy design pattern in C# is about what algorithm to use, while the State pattern is about when to change behavior based on internal state.

Strategy vs. Template Method Pattern

Both patterns deal with algorithm variations, but they approach it differently:

• Strategy Pattern: Uses composition to vary algorithms. The entire algorithm is encapsulated in a strategy class.
• Template Method Pattern: Uses inheritance to vary parts of an algorithm. The base class defines the algorithm structure, and subclasses override specific steps.

The Strategy design pattern in C# provides more flexibility at runtime, while the Template Method pattern provides more structure and code reuse through inheritance.

Benefits of Using Strategy Pattern

The Strategy design pattern in C# offers several significant benefits that make it valuable in C# applications. When implementing the Strategy design pattern in C#, you gain these advantages:

Eliminates Conditional Logic: Instead of using large if-else or switch statements to choose between algorithms, the Strategy design pattern in C# uses polymorphism. This makes code more maintainable and easier to understand. When you need to add a new algorithm, you simply create a new strategy class without modifying existing code.

Promotes Open/Closed Principle: The Strategy design pattern in C# allows you to extend functionality (add new strategies) without modifying existing code. This is a core principle of object-oriented design and makes your codebase more maintainable over time.

Improves Testability: Each strategy can be tested independently when using the Strategy design pattern in C#. You can create unit tests for individual strategies without needing to test the entire context. This makes it easier to ensure each algorithm works correctly.

Enhances Code Reusability: Strategies can be reused across different contexts when implementing the Strategy design pattern in C#. A single strategy implementation can be used by multiple context classes, reducing code duplication and improving maintainability.

Supports Runtime Algorithm Selection: Unlike compile-time decisions, the Strategy design pattern in C# allows you to select algorithms at runtime. This provides flexibility that's often needed in real-world applications where the best algorithm depends on runtime conditions.

Best Practices for Strategy Pattern

When implementing the Strategy design pattern in C#, following these best practices will help you create maintainable and effective solutions. These guidelines are based on real-world experience using the Strategy design pattern in C# applications:

Use Interfaces for Strategy Contracts: Define strategy interfaces that clearly express what each strategy must implement. This makes it easy to add new strategies and ensures all strategies follow the same contract. Interfaces also make strategies easier to test and mock when implementing the Strategy design pattern in C#. This approach follows the same interface-based design principles used in other patterns like the Adapter Design Pattern, which also relies heavily on interfaces for flexibility.

Keep Strategies Stateless When Possible: Stateless strategies are easier to test and can be reused across multiple contexts. If a strategy needs state, consider passing it as parameters rather than storing it in the strategy instance. This makes strategies more flexible and testable when using the Strategy design pattern in C#.

Use Dependency Injection: Inject strategies into context classes rather than creating them directly. This makes your code more testable and follows SOLID principles. Dependency injection frameworks can help manage strategy creation and lifecycle when implementing the Strategy design pattern in C#.

Document Strategy Selection Logic: If strategy selection is complex, document when and why each strategy should be used. This helps other developers understand the design decisions and makes maintenance easier. Consider using factory patterns or configuration to manage strategy selection when implementing the Strategy design pattern in C#.

Consider Strategy Composition: Sometimes, you may need to combine multiple strategies. Consider creating composite strategies that delegate to other strategies. This allows you to build complex behaviors from simpler strategies while maintaining the benefits of the Strategy design pattern in C#.

Common Pitfalls and How to Avoid Them

While the Strategy design pattern in C# is powerful, there are common pitfalls to avoid when implementing it. Understanding these pitfalls helps you use the Strategy design pattern in C# effectively:

Over-Engineering Simple Cases: Don't use the Strategy design pattern in C# for simple cases where a few if statements would suffice. The pattern adds complexity, so use it when you have multiple algorithms or expect to add more in the future. If you only have two options and they're unlikely to change, a simple conditional might be more appropriate.

Creating Too Many Small Strategies: While separation is good, creating too many tiny strategy classes can make code harder to navigate. Find a balance between separation and cohesion. Group related algorithms together when it makes sense when implementing the Strategy design pattern in C#.

Ignoring Strategy State Management: If strategies need to maintain state between calls, ensure you handle this properly. Stateless strategies are preferred, but when state is necessary, document it clearly and consider thread safety if applicable when using the Strategy design pattern in C#.

Not Considering Performance: Strategy design pattern in C# adds a layer of indirection, which can have performance implications in high-performance scenarios. Consider this when designing your system, but don't optimize prematurely. The flexibility often outweighs the small performance cost.

Real-World Example: Data Export System

Let's look at a complete real-world example: a data export system that can export data in different formats (CSV, JSON, XML) using the Strategy design pattern in C#.

// Strategy interface
public interface IDataExportStrategy
{
    string Export<T>(IEnumerable<T> data) where T : class;
    string GetFileExtension();
    string GetContentType();
}

// Concrete Strategies
public class CsvExportStrategy : IDataExportStrategy
{
    public string Export<T>(IEnumerable<T> data) where T : class
    {
        if (data == null || !data.Any())
        {
            return string.Empty;
        }

        var properties = typeof(T).GetProperties();
        var header = string.Join(",", properties.Select(p => p.Name));
        var rows = data.Select(item =>
            string.Join(",", properties.Select(p =>
            {
                var value = p.GetValue(item);
                return value?.ToString() ?? string.Empty;
            }))
        );

        return header + Environment.NewLine + string.Join(Environment.NewLine, rows);
    }

    public string GetFileExtension()
    {
        return ".csv";
    }

    public string GetContentType()
    {
        return "text/csv";
    }
}

public class JsonExportStrategy : IDataExportStrategy
{
    public string Export<T>(IEnumerable<T> data) where T : class
    {
        return System.Text.Json.JsonSerializer.Serialize(data, new JsonSerializerOptions
        {
            WriteIndented = true
        });
    }

    public string GetFileExtension()
    {
        return ".json";
    }

    public string GetContentType()
    {
        return "application/json";
    }
}

public class XmlExportStrategy : IDataExportStrategy
{
    public string Export<T>(IEnumerable<T> data) where T : class
    {
        if (data == null || !data.Any())
        {
            return "<?xml version="1.0" encoding="UTF-8"?><root></root>";
        }

        var xml = new System.Text.StringBuilder();
        xml.AppendLine("<?xml version="1.0" encoding="UTF-8"?>");
        xml.AppendLine("<root>");

        var properties = typeof(T).GetProperties();
        foreach (var item in data)
        {
            xml.AppendLine("  <item>");
            foreach (var prop in properties)
            {
                var value = prop.GetValue(item);
                xml.AppendLine($"    <{prop.Name}>{value}</{prop.Name}>");
            }
            xml.AppendLine("  </item>");
        }

        xml.AppendLine("</root>");
        return xml.ToString();
    }

    public string GetFileExtension()
    {
        return ".xml";
    }

    public string GetContentType()
    {
        return "application/xml";
    }
}

// Context class
public class DataExporter
{
    private IDataExportStrategy _exportStrategy;

    public DataExporter(IDataExportStrategy exportStrategy)
    {
        _exportStrategy = exportStrategy ?? throw new ArgumentNullException(nameof(exportStrategy));
    }

    public void SetExportStrategy(IDataExportStrategy exportStrategy)
    {
        _exportStrategy = exportStrategy;
    }

    public ExportResult ExportData<T>(IEnumerable<T> data, string fileName) where T : class
    {
        var content = _exportStrategy.Export(data);
        var fullFileName = fileName + _exportStrategy.GetFileExtension();

        return new ExportResult
        {
            Content = content,
            FileName = fullFileName,
            ContentType = _exportStrategy.GetContentType()
        };
    }
}

// Supporting class
public class ExportResult
{
    public string Content { get; set; }
    public string FileName { get; set; }
    public string ContentType { get; set; }
}

This example demonstrates how the Strategy design pattern in C# allows the DataExporter to support multiple export formats without modifying its core logic. Adding a new export format (like PDF or Excel) simply requires creating a new strategy class that implements IDataExportStrategy when implementing the Strategy design pattern in C#.

Integration with Other Design Patterns

The Strategy design pattern in C# often works well in combination with other design patterns:

Factory Pattern: Use a factory to create and select appropriate strategies based on configuration or runtime conditions. This centralizes strategy creation logic and makes it easier to manage strategy selection when implementing the Strategy design pattern in C#. Factory patterns are creational patterns that complement the Strategy design pattern in C# by handling the creation and selection of strategy instances.

Template Method Pattern: Combine Strategy with Template Method when you have a common algorithm structure but want to vary specific steps. The template method defines the structure, while strategies handle the variable parts. This combination leverages the strengths of both patterns in C# applications.

Decorator Pattern: Use decorators to add cross-cutting concerns (logging, caching, validation) to strategies without modifying the strategy implementations themselves. This is particularly useful when working with dependency injection frameworks and the Strategy design pattern in C#. The Facade Pattern provides another way to simplify complex interactions, while the Strategy design pattern in C# focuses on algorithm selection.

Understanding how the Strategy design pattern in C# relates to other design patterns helps you create more sophisticated and maintainable designs. The Strategy pattern is part of the behavioral design pattern family, alongside patterns like the State pattern and Template Method pattern, each serving different purposes in C# application design.

Conclusion

The Strategy design pattern in C# is a powerful tool for managing algorithm variations in C# applications. By encapsulating algorithms in separate strategy classes and making them interchangeable through a common interface, the Strategy design pattern in C# promotes flexibility, maintainability, and testability. Whether you're implementing payment processing, data export, or any scenario with multiple ways of performing the same operation, the Strategy design pattern in C# provides a clean solution that follows SOLID principles.

The key to successfully using the Strategy design pattern in C# is recognizing when algorithm variation is needed and when the pattern's benefits outweigh its complexity. For simple cases with few options, conditional logic may be sufficient. But when you have multiple algorithms, expect to add more in the future, or need runtime algorithm selection, the Strategy design pattern in C# is an excellent choice.

Remember that the Strategy design pattern in C# works exceptionally well with modern C# features like dependency injection, interfaces, and LINQ. By combining the Strategy pattern in C# with these language features and following best practices, you can create maintainable, testable, and flexible solutions that stand the test of time. The Strategy design pattern in C# is one of the most valuable patterns for creating flexible, maintainable code in .NET applications.

Frequently Asked Questions

What is the main difference between Strategy and State patterns?

The Strategy design pattern in C# is about what algorithm to use, while the State pattern is about when to change behavior based on internal state. In Strategy, algorithms are chosen externally by the client and are independent of each other. In State, states are part of an object's lifecycle, know about other states, and can transition between them based on internal conditions.

Can I use Strategy pattern with value types in C#?

While you can use the Strategy design pattern in C# with value types, it's more common and effective with reference types (classes) because strategies are typically objects. However, you can use delegates or function pointers as lightweight strategies for simple cases. For complex scenarios, prefer class-based strategies for better testability and maintainability when implementing the Strategy design pattern in C#.

How do I choose between Strategy pattern and simple if-else statements?

Use the Strategy design pattern in C# when you have multiple algorithms, expect to add more in the future, need runtime algorithm selection, or want better testability and maintainability. Use simple conditionals when you have only two or three options that are unlikely to change and the logic is straightforward. The pattern adds complexity, so ensure the benefits justify it when implementing the Strategy design pattern in C#.

Is Strategy pattern thread-safe?

The Strategy design pattern in C# itself doesn't guarantee thread safety. If strategies maintain state, you need to ensure thread safety yourself. Prefer stateless strategies when possible, as they're naturally thread-safe. If state is necessary, use appropriate synchronization mechanisms or ensure strategies are used within thread-safe contexts when implementing the Strategy design pattern in C#.

Can strategies depend on each other?

Strategies should generally be independent of each other when implementing the Strategy design pattern in C#. If strategies need to work together, consider using composition to create composite strategies that delegate to other strategies. This maintains the benefits of the Strategy design pattern in C# while allowing complex behaviors. Avoid direct dependencies between strategies, as this reduces flexibility and testability.

How does Strategy pattern relate to dependency injection?

The Strategy design pattern in C# works exceptionally well with dependency injection. You can register strategies in your DI container and inject them into context classes. This makes strategies more testable, allows for easier strategy swapping, and follows SOLID principles. Many modern C# applications use this combination for flexible, maintainable designs when implementing the Strategy design pattern in C#.

What are the performance implications of Strategy pattern?

The Strategy design pattern in C# adds a layer of indirection (method calls through interfaces), which has a small performance cost compared to direct method calls or inline code. However, this cost is typically negligible in most applications. The flexibility and maintainability benefits usually outweigh the small performance overhead when implementing the Strategy design pattern in C#. Only optimize if profiling shows it's a bottleneck.