In ASP.NET, dependency injection (DI) lifecycles determine the lifetime of objects that are resolved through the DI container. There are several predefined lifecycle options in the `Microsoft.Extensions.DependencyInjection` library, including:
- **Transient:** A new instance of the object is created every time it is requested.
- **Scoped:** A new instance of the object is created for each request within the same scope.
- **Singleton:** A single instance of the object is created and shared across the entire application.
Additionally, you can also create a custom lifecycle by implementing the `Microsoft.Extensions.DependencyInjection.IServiceScopeFactory` interface