/// /// <summary>
/// Initializes a new instance of the <see cref="DelegateServiceLocator" /> class.
/// </summary>
/// <param name="baseLocator">The value for <see cref="DelegateServiceLocator.BaseLocator" /> property.</param>
/// <param name="multiFallback">The value for <see cref="DelegateServiceLocator.MultiInstanceFallback" /> property.</param>
/// <param name="singleFallback">The value for <see cref="DelegateServiceLocator.SingleInstanceFallback" /> property.</param>
/// <param name="syncRoot">The value for the <see cref="ServiceLocatorBase._SYNC_ROOT" /> field.</param>
public DelegateServiceLocator(IServiceLocator baseLocator = null,
MultiInstanceFallbackProvider multiFallback = null, SingleInstanceFallbackProvider singleFallback = null,
object syncRoot = null)
: base(syncRoot: syncRoot)
{
this.BaseLocator = baseLocator;
this.MultiInstanceFallback = multiFallback;
this.SingleInstanceFallback = singleFallback;
}
// Protected Methods (2)
/// <inheriteddoc />
protected override IEnumerable <object> OnGetAllInstances(Type serviceType, object key)
{
IEnumerable <object> result = null;
InstanceProvider provider;
if (this._MULTI_PROVIDERS.TryGetValue(serviceType, out provider))
{
IEnumerable seq = provider.Invoke <IEnumerable>(this.BaseLocator,
key);
if (seq != null)
{
result = CollectionHelper.AsSequence <object>(seq);
}
if (result == null)
{
throw new ServiceActivationException(serviceType, key);
}
}
bool tryFallback = true;
if (result == null)
{
if (this._BASE_LOCATOR != null)
{
// use base service locator instead
tryFallback = false;
result = this._BASE_LOCATOR
.GetAllInstances(serviceType, key);
}
}
if (tryFallback)
{
// try by fallback, if defined
MultiInstanceFallbackProvider fb = this.MultiInstanceFallback;
if (fb != null)
{
result = fb(this, key, serviceType);
}
}
return(result);
}
