API Reference

Global accessor

function GetInjector: TInject;

Returns the process-wide TInject instance. Thread-safe: acquires GInjectorLock before returning the pointer. Returns nil if the injector has been destroyed.

TInject — Registration methods

Singleton

procedure Singleton<T: class, constructor>(
  const AOnCreate: TProc<T> = nil;
  const AOnDestroy: TProc<T> = nil;
  const AOnConstructorParams: TConstructorCallback = nil); overload;

Registers T as a Singleton. The instance is created immediately and stored. Raises Exception if T is already registered.

SingletonLazy

procedure SingletonLazy<T: class>(
  const AOnCreate: TProc<T> = nil;
  const AOnDestroy: TProc<T> = nil;
  const AOnConstructorParams: TConstructorCallback = nil);

Registers T as a lazy Singleton. No instance is created at registration; construction is deferred to the first Get<T> call. Raises EServiceAlreadyRegistered if already registered.

SingletonInterface

procedure SingletonInterface<I: IInterface; T: class, constructor>(
  const ATag: string = '';
  const AOnCreate: TProc<T> = nil;
  const AOnDestroy: TProc<T> = nil;
  const AOnConstructorParams: TConstructorCallback = nil);

Registers the interface I → implementation T mapping. The interface I must declare a GUID. Resolution key: GUIDToString(GetTypeData(TypeInfo(I)).Guid), or ATag if non-empty. Raises EServiceAlreadyRegistered if already registered.

Factory

procedure Factory<T: class, constructor>(
  const AOnCreate: TProc<T> = nil;
  const AOnDestroy: TProc<T> = nil;
  const AOnConstructorParams: TConstructorCallback = nil);

Registers T as a Factory. A new instance is constructed on every Get<T> call. Raises Exception if already registered.

AddInject

procedure AddInject(const ATag: string; const AInstance: TInject);

Registers another TInject as a child injector under ATag. Resolution cascades into child injectors when the parent cannot find a service. Raises EServiceAlreadyRegistered if ATag is already in use.

AddInstance

procedure AddInstance<T: class>(const AInstance: TObject);

Registers an already-constructed object as a Singleton under T.ClassName. The container takes ownership (frees the instance on removal or destruction). Raises EServiceAlreadyRegistered if already registered.

---

TInject — Resolution methods

Get

function Get<T: class, constructor>(const ATag: string = ''): T;

Resolves the registered service for T (or ATag if non-empty). Returns nil if not found (does not raise). Cascades into child injectors.

GetInterface

function GetInterface<I: IInterface>(const ATag: string = ''): I;

Resolves the registered interface I. Raises EServiceNotFound if not registered anywhere in the injector tree.

GetInstances

function GetInstances: TObjectDictionary<string, TServiceData>;

Returns the internal instance dictionary. For diagnostics only — do not modify.

---

TInject — Maintenance methods

Remove

procedure Remove<T: class>(const ATag: string = '');

Fires OnDestroy (if registered), removes all entries for T / ATag from internal dictionaries, and frees the singleton instance.

EnableLogging

procedure EnableLogging(const ALogCallback: TProc<string> = nil);

Activates operation logging. If ALogCallback is nil, log messages are generated but not delivered anywhere (useful if you wire the callback later).

DisableLogging

procedure DisableLogging;

Deactivates logging and clears FLogCallback.

ClearCache

procedure ClearCache;

Clears FTypeCache and FMethodCache under FRttiCacheLock. Does not destroy FRttiContext.

---

Exceptions

Exception class	Parent	Raised when
EInjectException	Exception	Base for all InjectContainer exceptions
EServiceAlreadyRegistered	EInjectException	Duplicate registration
EServiceNotFound	EInjectException	GetInterface<I> cannot find I
ECircularDependency	EInjectException	Circular dependency detected in resolution stack

---

Types

Type	Declaration	Description
TInjectionMode	(imSingleton, imFactory)	Lifecycle mode stored in TServiceData
TConstructorParams	TArray<TValue>	Parameter array passed to RTTI constructor call
TConstructorCallback	TFunc<TConstructorParams>	Callback that returns constructor parameters
TConstructorEvents	TObjectDictionary<string, TInjectEvents>	Container-level event dictionary type

---

TServiceData (internal)

TServiceData is the internal descriptor for every registered service. It is not part of the public surface but its behavior drives resolution:

Method	Purpose
GetInstance<T>(Events, Params)	Returns cached or new instance based on TInjectionMode
GetInterface<I>(Key, Events, Params)	Returns cached interface value
AsInstance	Returns FInstance as TObject
ServiceClass	Returns the registered TClass
InjectionMode	Returns TInjectionMode