Dependency Abstraction for Testability

Snippet

Dependency Abstraction for Testability

By injecting interfaces instead of concrete classes, you decouple your code, making it easy to swap real implementations with mocks during testing.

snippet.cs

csharp

public interface IDatabase { void Save(string data); }
 
public class DataService
{
    private readonly IDatabase _db;
    public DataService(IDatabase db) => _db = db;
 
    public void Process(string input)
    {
        // Logic here
        _db.Save(input);
    }
}

Breakdown

private readonly IDatabase _db;

Declares a private field for the interface to store the injected dependency.

public DataService(IDatabase db)

The constructor requires an implementation of IDatabase, facilitating dependency injection.

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Dependency Abstraction for Testability

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