• Avalanche
  • Avalanche.Core
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    • Avalanche.Localization
      • Introduction
      • Localization
      • LocalizationFile
      • LocalizationFiles
      • LocalizationFileSystem
      • LocalizationFileFormat
      • LocalizationLine
      • LocalizationLines
      • TemplateFormat
      • CultureProvider
      • FallbackCultureProvider
      • ResourceManager
      • LocalizationError
      • Microsoft.Extensions
        • Introduction
        • DependencyInjection
        • FileProvider
        • Logging
        • ITextLocalizer
        • IFileLocalizer
        • Localization
        • AspNetCore
      • Pluralization
        • Introduction
        • Multiple plural parameters
        • Custom PluralRules
        • Invariant Culture
        • Unit Prefix
        • IPluralRule
        • IPluralNumber
        • IPluralRules
        • CLDRs
        • Unicode.CLDR41
        • Unicode.CLDR40
      • Articles
        • Alphabet localization
        • Benchmarks
        • Caching
        • Class Library
        • Demo
        • Diagnostics
        • Embedded resources
        • Emplacement
        • File localization
        • Text localization
    • Avalanche.Message
      • Introduction
      • IMessage
      • IMessageProvider
      • IMessageDescription
      • IMessageDescriptions
      • MessageLevel
      • Message printing
      • Messages and Exceptions
      • Logging
      • Validation
      • Localization
    • Avalanche.StatusCode
      • Introduction
      • HResult
        • Introduction
        • HResult.Facilities
        • BasicMessages
        • RpcMessages
        • DispatchMessages
        • ItfMessages
        • Win32Messages
        • ClrMessages
      • System
        • Introduction
        • AccessControlMessages
        • AggregateMessages
        • AppDomainMessages
        • ArgumentMessages
        • ArgumentNullMessages
        • ArgumentOutOfRangeMessages
        • ArithmeticMessages
        • ArrayMessages
        • AssemblyMessages
        • BadImageFormatMessages
        • CodeContractMessages
        • CodePageMessages
        • CollectionsMessages
        • CompilerServiceMessages
        • CryptographyMessages
        • CultureMessages
        • DiagnosticsMessages
        • EventSourceMessages
        • ExecutionEngineMessages
        • FormatMessages
        • HostProtectionMessages
        • IOMessages
        • IndexOutOfRangeMessages
        • InteropServiceMessages
        • InvalidCastMessages
        • InvalidOperationMessages
        • IsolatedStorageMessages
        • LazyMessages
        • MarshalerMessages
        • MemoryMessages
        • MiscellaneousMessages
        • NotImplementedMessages
        • NotSupportedMessages
        • ObjectDisposedMessages
        • OperationCanceledMessages
        • OverflowMessages
        • PlatformMessages
        • PolicyMessages
        • PrincipalMessages
        • ProgramMessages
        • ReferenceMessages
        • ReflectionMessages
        • RegionMessages
        • RemotingMessages
        • ResourcesMessages
        • SecurityMessages
        • SerializationMessages
        • StackMessages
        • TaskMessages
        • TextMessages
        • ThreadingMessages
        • TimeZoneMessages
        • TypeMessages
        • XmlMessages
    • Avalanche.Template
      • Introduction
      • TemplateFormats
      • ITemplatePrintable
      • ITemplateFormatPrintable
      • ITemplateText
      • ITemplateBreakdown
      • ITemplateFormat
      • ITemplateFormats
      • Extract Arguments
      • Emplacement
    • Avalanche.Tokenizer
      • Introduction
      • IToken
      • ITokenizer
      • Tokenizers
    • Avalanche.Service
      • Introduction
      • Service
        • IService
        • Construction
        • Query
        • CancellationToken
        • CachePolicy
        • Cast
        • Scope
        • Dispose
      • Handler
        • Introduction
        • IHandler
        • Cancel
        • Recursion
        • Cyclicity
        • Delegates
        • Casting
        • Invokable
        • Handlers
      • Request
        • Introduction
        • IRequest
        • [Request]
        • [ContextParameter]
        • Print Tree
      • Dependency Injection
        • Introduction
        • ServiceRequest<T>
        • Handler
        • CachePolicy
        • CancellationToken
        • QueryLogger
      • Examples
        • Expression Example
        • Mapper Example
      • ServiceMessages
    • Avalanche.Writer
      • Introduction
      • Writer
      • Referer
      • TypeCast
      • DefaultConstructor
      • DelegateWriter
      • WriterPipe
      • ConstantWriter
      • PassthroughWriter
      • Context
      • WriterMessages
    • Avalanche.Accessor
      • Introduction
      • AccessorServices
      • List
        • ListAccessor
        • ListConstructor
        • ListDeconstructor
        • ListDefaultConstructor
        • ListGet
        • ListSet
        • ListAdd
        • ListInsert
        • ListClear
        • ListCount
        • ListIndexOf
        • ListRemoveAt
        • ListReferer
      • Map
        • MapAccessor
        • MapConstructor
        • MapDeconstructor
        • MapDefaultConstructor
        • MapSet
        • MapGet
        • MapRemove
        • MapClear
        • MapCount
        • MapReferer
      • Record
        • RecordAccessor
        • RecordConstructor
        • RecordDeconstructor
        • RecordDefaultConstructor
      • Field
        • FieldAccessor
        • FieldReader
        • FieldWriter
        • FieldReferer
      • Dependency Injection
        • Introduction
      • AccessorMessages
    • Avalanche.Emit
      • Introduction
      • TypeBuilder
      • ConstructorBuilder
      • MethodBuilder
      • PropertyBuilder
      • FieldBuilder
      • Emit
      • Utilities
    • Avalanche.DataType
      • Introduction
      • IDataTypeBase
      • IDataType
      • IRecordType
      • IFieldType
      • IUnionType
      • IListType
      • IMapType
      • IValueType
      • IEnumerationType
      • IIntegerType
      • IRealType
      • IStringType
      • IAnyType
      • DataTypeRequest
      • PrintTree
      • DataTypeMessages
    • Avalanche.FileSystem
      • Introduction
      • Abstractions
        • IFileSystem
          • IFileSystemBrowse
          • IFileSystemCreateDirectory
          • IFileSystemDelete
          • IFileSystemFileAttribute
          • IFileSystemMount
          • IFileSystemMove
          • IFileSystemObserve
          • IFileSystemOpen
        • IEvent
        • IEntry
        • IOption
        • IToken
      • FileSystem
      • VirtualFileSystem
      • MemoryFileSystem
      • EmbeddedFileSystem
      • HttpFileSystem
      • Decoration
      • IFileProvider
      • Events
      • Utilities
        • Dispose
        • File Scanner
        • Visit Tree
        • File Operation
    • Avalanche.Identity
      • Introduction
      • Identity
      • IdentityParts
      • IdentityInterner
      • IdentityComparer
      • Print Tree
      • IdentityAccessors
        • Introduction
        • TypeName
    • Avalanche.Utilities
      • Introduction
      • Collections
        • Tuples
        • StructList
        • ArrayList
        • BijectionMap
        • LocakableDictionary
        • LockableList
        • MapList
        • Pipe
        • RingQueue
        • EnumerableExtensions
        • TupleUtilities
        • ArrayUtilities
      • Comparers
        • IGraphComparer
        • IGraphComparable
        • AlphaNumericComparer
        • EnumerableComparer
        • EnumerableGraphComparer
        • ReferenceComparer
        • KeyValuePairComparer
        • DefaultComparerProvider
        • RecordComparer
      • Cloners
        • ICloner
        • IGraphCloner
        • IGraphCloneable
        • EnumerableCloner
        • FieldCloner
        • PassthroughCloner
        • RecordCloner
        • ClonerProvider
      • Dispose
        • IDisposeAttachable
        • IDisposeBelatable
      • Provider
        • Introduction
        • ProviderBase
        • Delegate
        • Concatenation
        • Cache
        • ResultCapture
        • AsReadOnly
        • AsService
      • Record
        • IRecordDescription
        • IFieldDescription
        • IConstructorDescription
        • IConstructionDescription
        • IParameterDescription
        • IRecordProviders
        • RecordDelegates
          • RecordCreate
          • RecordClone
          • RecordCopy
          • IRecordDelegates
        • FieldDelegates
          • FieldRead
          • FieldWrite
          • RecreateWith
          • IFieldDelegates
      • String
        • IEscaper
        • UnicodeString
      • Miscellaneous
        • IIdGenerator
        • Permutation
        • IReadOnly
        • IUserDataContainer
        • Void
    • Avalanche.Core
      • License
      • Order

    Casting

    Handler can be casted into other interfaces.

    // Create generics handler
    IHandler consoleLogger = new ConsoleLogger();
    // Cast to IHandler<object, object>
    consoleLogger.TryCast(out IHandler<object, object>? castedHandler);
    

    IServiceBase.AsHandler() extension method casts into IHandlerBase.

    // Create service
    IService service = Services.Create(new ConverterHandlers());
    // Cast to handler
    IHandler handler = service.AsHandler();
    

    IEntryProviderBase.AsHandler() extension method casts into IHandlerBase.

    // Create entry provider
    IEntryProvider entryProvider = (IEntryProvider)Services.Create(new ConverterHandlers());
    // Cast to handler
    IHandlerBase handler = Handlers.EntryProvider(entryProvider);
    

    If handler implements IHandlerCastable, it can explicity participate in casting instantiation.

    public class Handler21 : IHandler, IHandlerCastable
    {
        public void Handle<Request, Response>(IQuery<Request, Response> query) where Request : notnull
            => Console.WriteLine(query.Response);
    
        public bool TryCast([NotNullWhen(true)] out IHandler casted) { casted = null!; return false; }
        public bool TryCast<Request, Response>([NotNullWhen(true)] out IHandler<Request, Response> casted) where Request : notnull { casted = null!; return false; }
        public bool TryCastAsync([NotNullWhen(true)] out IHandlerAsync casted) { casted = null!; return false; }
        public bool TryCastAsync<Request, Response>([NotNullWhen(true)] out IHandlerAsync<Request, Response> casted) where Request : notnull { casted = null!; return false; }
    }
    

    Full Example

    Full example
    using System;
    using System.Diagnostics.CodeAnalysis;
    using Avalanche.Converter;
    using Avalanche.Service;
    
    public class handler_casting
    {
        public static void Run()
        {
            {
                // <1>
                // Create generics handler
                IHandler consoleLogger = new ConsoleLogger();
                // Cast to IHandler<object, object>
                consoleLogger.TryCast(out IHandler<object, object>? castedHandler);
                // </1>
            }
    
            {
                // <2>
                // Create service
                IService service = Services.Create(new ConverterHandlers());
                // Cast to handler
                IHandlerBase handler = Handlers.Service(service);
                // </2>
            }
    
            {
                // <3>
                // Create service
                IService service = Services.Create(new ConverterHandlers());
                // Cast to handler
                IHandler handler = service.AsHandler();
                // </3>
            }
    
            {
                // <4>
                // Create entry provider
                IEntryProvider entryProvider = (IEntryProvider)Services.Create(new ConverterHandlers());
                // Cast to handler
                IHandlerBase handler = Handlers.EntryProvider(entryProvider);
                // </4>
            }
            {
                // <5>
                // Create entry provider
                IEntryProvider entryProvider = (IEntryProvider)Services.Create(new ConverterHandlers());
                // Cast to handler
                IHandler handler = entryProvider.AsHandler();
                // </5>
            }
        }
    
        // <6>
        public class ConsoleLogger : IHandler
        {
            public void Handle<Request, Response>(IQuery<Request, Response> query) where Request : notnull
                => Console.WriteLine(query.Response);
        }
        // </6>
    
        // <7>
        public class Handler21 : IHandler, IHandlerCastable
        {
            public void Handle<Request, Response>(IQuery<Request, Response> query) where Request : notnull
                => Console.WriteLine(query.Response);
    
            public bool TryCast([NotNullWhen(true)] out IHandler casted) { casted = null!; return false; }
            public bool TryCast<Request, Response>([NotNullWhen(true)] out IHandler<Request, Response> casted) where Request : notnull { casted = null!; return false; }
            public bool TryCastAsync([NotNullWhen(true)] out IHandlerAsync casted) { casted = null!; return false; }
            public bool TryCastAsync<Request, Response>([NotNullWhen(true)] out IHandlerAsync<Request, Response> casted) where Request : notnull { casted = null!; return false; }
        }
        // </7>
    }
    
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