ContainerRegisterConditionalTService, TImplementation Method (PredicatePredicateContext)

Simple Injector

Conditionally registers that a new instance of TImplementation will be returned every time a TService is requested (transient) and where the supplied predicate returns true. The predicate will only be evaluated a finite number of times; the predicate is unsuited for making decisions based on runtime conditions.

Namespace: SimpleInjector
Assembly: SimpleInjector (in SimpleInjector.dll) Version: 5.3.0

Syntax

ASP.NET

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public void RegisterConditional<TService, TImplementation>(
	Predicate<PredicateContext> predicate
)
where TService : class
where TImplementation : class, TService

Public Sub RegisterConditional(Of TService As Class, TImplementation As {Class, TService}) ( 
	predicate As Predicate(Of PredicateContext)
)

Parameters

predicate: Type: SystemPredicatePredicateContext
The predicate that determines whether the TImplementation can be applied for the requested service type. This predicate can be used to build a fallback mechanism where multiple registrations for the same service type are made. Note that the predicate will be called a finite number of times and its result will be cached for the lifetime of the container. It can't be used for selecting a type based on runtime conditions.

Type Parameters

TService: The interface or base type that can be used to retrieve the instances.
TImplementation: The concrete type that will be registered.

Exceptions

Exception	Condition
ArgumentNullException	Thrown when one of the arguments is a null reference.
InvalidOperationException	Thrown when this container instance is locked and can not be altered.

Remarks

This method uses the container's LifestyleSelectionBehavior to select the exact lifestyle for the specified type. By default this will be Transient.

Reference

Container Class

RegisterConditional Overload

SimpleInjector Namespace