How deeply does ASP.NET Core in Action, 3e cover OptionsBuilder ?

Explains builder creation, configuration chaining, dependency resolution, and an IConfigureOptions alternative, but does not detail validation rules.

OptionsBuilder<T>

As explained in ASP.NET Core in Action, 3e

OptionsBuilder<T> is a .NET options API type that fluently composes configuration and validation for an options type and can resolve dependencies for configuration actions.

OptionsBuilder<T> provides a fluent way to create and configure strongly typed IOptions<T> objects. Start with AddOptions<T>(), then chain calls such as BindConfiguration and Configure to combine configuration binding with code-based settings. section 31.2 section 31.4

Bind configuration and add code-based settings

builder.Services .AddOptions<CurrencyOptions>() .BindConfiguration("Currencies") .Configure(opts => opts.Currencies = new[] { "GBP", "USD" }); When a dependent service requests IOptions<CurrencyOptions>, the framework creates the options object, applies the registered configuration steps, and exposes the result through opts.Value. section 31.2 section 31.2

OptionsBuilder<T> can resolve dependencies from dependency injection while running a configuration action. Register the dependency, then use a Configure<TDependency> overload to populate the options from that service. For more separation, implement IConfigureOptions<T> and inject the dependency into its constructor. The builder also supports options validation. section 31.2 section 31.4

How ASP.NET Core in Action, 3e covers it

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Related concepts

IConfigureOptions<T>alternative to · IConfigureOptions<T> is a .NET interface implemented by components that configure instances of an options type.
AddOptions<T>()produced by · AddOptions<T>() is an ASP.NET Core service-collection extension method that creates an OptionsBuilder<T> for configuring an options type.
IOptions<T>produces · IOptions<T> is a .NET interface that provides access to a configured strongly typed options object.
dependency injectionuses · Dependency injection is a software design technique in which a component receives its dependencies from outside rather than creating or locating them internally.
builder patternuses · The builder pattern is a creational design pattern that constructs a complex object through separate, stepwise configuration and assembly operations.

This explainer was generated by Manning's knowledge graph from the text of ASP.NET Core in Action, 3e. The section links point to the parts of the book it draws on.