ExportComponentManager

Namespace: TagBites.ComponentModel.Composition
Assembly: TagBites.ComponentModel.Composition.dll
Product: TagBites.ComponentModel.Composition v. 1.2.1

Container of exported components. Discovers types marked with ExportAttribute and creates their instances on demand.

public class ExportComponentManager

Inheritance: object → ExportComponentManager

Remarks

All members are thread safe.

Constructors

ExportComponentManager()

public ExportComponentManager()

Properties

AssemblyCacheDirectory

Gets the directory with assembly cache files, or null when the cache is not used.

public string AssemblyCacheDirectory { get; }

Property Value

string

Methods

AddNotify(Type, EventHandler)

Adds a handler called when the exports of the given contract type change.

public void AddNotify(Type contractType, EventHandler handler)

Parameters

contractType Type
Contract type to watch.
handler EventHandler
Handler to add.

CreateExportInstance<T>(Uri)

Creates a new instance of the export with the given location.

public T CreateExportInstance(Uri location)

Type Parameters

T
Contract type.

Parameters

location Uri
Export URI.

Returns

New instance, or the default value of T when no such export exists.

CreateExportInstance(Uri)

Creates a new instance of the export with the given location.

public object CreateExportInstance(Uri location)

Parameters

location Uri
Export URI.

Returns

object

New instance, or the default value of T when no such export exists.

CreateExportInstances<T>()

Creates a new instance of every export of the given contract.

public IEnumerable<T> CreateExportInstances()

Type Parameters

T
Contract type.

Returns

IEnumerable<T>

New instances of exports without a contract name.

CreateExportInstances<T>(string)

Creates a new instance of every export of the given contract.

public IEnumerable<T> CreateExportInstances(string contractName)

Type Parameters

T
Contract type.

Parameters

contractName string
Contract name, or null for exports without a contract name.

Returns

IEnumerable<T>

New instances.

CreateExportInstances(ContractDefinition)

Creates a new instance of every export of the given contract.

public IEnumerable<object> CreateExportInstances(ContractDefinition contract)

Parameters

contract ContractDefinition

Returns

IEnumerable<object>

New instances.

CreateExportInstances(Type)

Creates a new instance of every export of the given contract.

public IEnumerable<object> CreateExportInstances(Type contractType)

Parameters

contractType Type

Returns

IEnumerable<object>

New instances.

CreateExportInstances(string, Type)

Creates a new instance of every export of the given contract.

public IEnumerable<object> CreateExportInstances(string contractName, Type contractType)

Parameters

contractName string
Contract name, or null for exports without a contract name.
contractType Type

Returns

IEnumerable<object>

New instances.

CreateManyExportInstances<T>(string[])

Creates a new instance of every export of the given contract names.

public IEnumerable<T> CreateManyExportInstances(string[] contractNames)

Type Parameters

T
Contract type.

Parameters

contractNames string[]
Contract names. A null item means exports without a contract name; duplicates are ignored.

Returns

IEnumerable<T>

New instances.

CreateManyExportInstances(string[], Type)

Creates a new instance of every export of the given contract names.

public IEnumerable<object> CreateManyExportInstances(string[] contractNames, Type contractType)

Parameters

contractNames string[]
Contract names. A null item means exports without a contract name; duplicates are ignored.
contractType Type

Returns

IEnumerable<object>

New instances.

GetExport<T>(Uri)

Gets the export with the given location.

public ExportComponent<T> GetExport(Uri location)

Type Parameters

T
Contract type.

Parameters

location Uri
Export URI.

Returns

ExportComponent<T>

Export component, or null when no such export exists or its contract type differs.

GetExport(Uri)

Gets the export with the given location. Follows the override chain, so the last export registered for the location wins.

public ExportComponent GetExport(Uri location)

Parameters

location Uri
Export URI.

Returns

ExportComponent

Export component, or null when no such export exists.

GetExportInstance<T>(Uri)

Gets the shared instance of the export with the given location.

public T GetExportInstance(Uri location)

Type Parameters

T
Contract type.

Parameters

location Uri
Export URI.

Returns

Shared instance, or the default value of T when no such export exists.

GetExportInstance(Uri)

Gets the shared instance of the export with the given location.

public object GetExportInstance(Uri location)

Parameters

location Uri
Export URI.

Returns

object

Shared instance, or the default value of T when no such export exists.

GetExportInstances<T>()

Gets the shared instances of all exports of the given contract.

public IEnumerable<T> GetExportInstances()

Type Parameters

T
Contract type.

Returns

IEnumerable<T>

Shared instances of exports without a contract name.

GetExportInstances<T>(string)

Gets the shared instances of all exports of the given contract.

public IEnumerable<T> GetExportInstances(string contractName)

Type Parameters

T
Contract type.

Parameters

contractName string
Contract name, or null for exports without a contract name.

Returns

IEnumerable<T>

Shared instances.

GetExportInstances(ContractDefinition)

Gets the shared instances of all exports of the given contract.

public IEnumerable<object> GetExportInstances(ContractDefinition contract)

Parameters

contract ContractDefinition

Returns

IEnumerable<object>

Shared instances.

GetExportInstances(Type)

Gets the shared instances of all exports of the given contract.

public IEnumerable<object> GetExportInstances(Type contractType)

Parameters

contractType Type

Returns

IEnumerable<object>

Shared instances.

GetExportInstances(string, Type)

Gets the shared instances of all exports of the given contract.

public IEnumerable<object> GetExportInstances(string contractName, Type contractType)

Parameters

contractName string
Contract name, or null for exports without a contract name.
contractType Type

Returns

IEnumerable<object>

Shared instances.

GetExports<T>()

Gets all exports of the given contract.

public IEnumerable<ExportComponent<T>> GetExports()

Type Parameters

T
Contract type.

Returns

IEnumerable<ExportComponent<T>>

Exports without a contract name.

GetExports<T>(string)

Gets all exports of the given contract.

public IEnumerable<ExportComponent<T>> GetExports(string contractName)

Type Parameters

T
Contract type.

Parameters

contractName string
Contract name, or null for exports without a contract name.

Returns

IEnumerable<ExportComponent<T>>

Exports.

GetExports(ContractDefinition)

Gets all exports of the given contract.

public IEnumerable<ExportComponent> GetExports(ContractDefinition contract)

Parameters

contract ContractDefinition

Returns

IEnumerable<ExportComponent>

Exports.

GetExports(Type)

Gets all exports of the given contract.

public IEnumerable<ExportComponent> GetExports(Type contractType)

Parameters

contractType Type

Returns

IEnumerable<ExportComponent>

Exports.

GetExports(string, Type)

Gets all exports of the given contract.

public IEnumerable<ExportComponent> GetExports(string contractName, Type contractType)

Parameters

contractName string
Contract name, or null for exports without a contract name.
contractType Type

Returns

IEnumerable<ExportComponent>

Exports.

GetExports(Assembly)

Gets all exports that come from the given assembly.

public IList<ExportComponent> GetExports(Assembly assembly)

Parameters

assembly Assembly
Origin assembly.

Returns

IList<ExportComponent>

Exports.

GetExportsDefinitions(Assembly)

Gets the definitions of all exports whose value type comes from the given assembly.

public IList<ExportComponentDefinition> GetExportsDefinitions(Assembly assembly)

Parameters

assembly Assembly
Value type assembly.

Returns

IList<ExportComponentDefinition>

Export definitions.

Remarks

Resolves the value type of every export, which loads types that the cache left unresolved.

GetLoadedAssemblies()

Gets the assemblies loaded into the container.

public Assembly[] GetLoadedAssemblies()

Returns

Assembly[]

Loaded assemblies.

GetManyExportInstances<T>(string[])

Gets the shared instances of all exports of the given contract names.

public IEnumerable<T> GetManyExportInstances(string[] contractNames)

Type Parameters

T
Contract type.

Parameters

contractNames string[]
Contract names. A null item means exports without a contract name; duplicates are ignored.

Returns

IEnumerable<T>

Shared instances.

GetManyExportInstances(string[], Type)

Gets the shared instances of all exports of the given contract names.

public IEnumerable<object> GetManyExportInstances(string[] contractNames, Type contractType)

Parameters

contractNames string[]
Contract names. A null item means exports without a contract name; duplicates are ignored.
contractType Type

Returns

IEnumerable<object>

Shared instances.

GetManyExports<T>(string[])

Gets all exports of the given contract names.

public IEnumerable<ExportComponent<T>> GetManyExports(string[] contractNames)

Type Parameters

T
Contract type.

Parameters

contractNames string[]
Contract names. A null item means exports without a contract name; duplicates are ignored.

Returns

IEnumerable<ExportComponent<T>>

Exports.

GetManyExports(string[], Type)

Gets all exports of the given contract names.

public IList<ExportComponent> GetManyExports(string[] contractNames, Type contractType)

Parameters

contractNames string[]
Contract names. A null item means exports without a contract name; duplicates are ignored.
contractType Type

Returns

IList<ExportComponent>

Exports.

LoadAssembly(Type)

Loads all exports of the given assembly. Does nothing when the assembly is already loaded.

public void LoadAssembly(Type typeInRequestedAssembly)

Parameters

typeInRequestedAssembly Type
Any type from the assembly to load.

Remarks

Reads the export definitions from the cache when a matching cache file exists, otherwise reflects over all types of the assembly. Either all exports of the assembly become available, or none: a failure unloads the assembly and rethrows.

LoadAssembly(Assembly)

Loads all exports of the given assembly. Does nothing when the assembly is already loaded.

public void LoadAssembly(Assembly assembly)

Parameters

assembly Assembly
Assembly to load.

Remarks

PrepareCache()

Writes cache files for the assemblies that were loaded through reflection and deletes the files of their earlier builds.

public void PrepareCache()

Exceptions

InvalidOperationException - UseCache(string, Func, Action) was not called.

Remarks

Call after startup, for example from a background task.

Register<T>(ExportComponent<T>)

Registers a component that no assembly declares.

public void Register(ExportComponent<T> component)

Type Parameters

T
Contract type.

Parameters

component ExportComponent<T>
Component to register.

Exceptions

InvalidOperationException - An export with the same location is already registered.

RemoveNotify(Type, EventHandler)

Removes a handler added by AddNotify(Type, EventHandler).

public void RemoveNotify(Type contractType, EventHandler handler)

Parameters

contractType Type
Watched contract type.
handler EventHandler
Handler to remove.

UnloadAssembly(Assembly)

Removes all exports of the given assembly and restores the exports it replaced. Does nothing when the assembly is not loaded.

public void UnloadAssembly(Assembly assembly)

Parameters

assembly Assembly
Assembly to unload.

Unregister(Uri)

Removes the export with the given location.

public bool Unregister(Uri location)

Parameters

location Uri
Export URI.

Returns

bool

true when an export was removed.

Unregister(ExportComponent)

Removes a registered component. Exports that come from an assembly stay untouched.

public bool Unregister(ExportComponent component)

Parameters

component ExportComponent
Component to remove.

Returns

bool

true when the component was removed.

UseCache(string, Func<string, Type, object>, Action<string, object>)

Turns on the assembly cache, which replaces reflection over all types with reading one file per assembly.

public void UseCache(string assemblyCacheDirectory, Func<string, Type, object> deserializeFromFile, Action<string, object> serializeToFile)

Parameters

assemblyCacheDirectory string
Directory with the cache files.
deserializeFromFile Func<string, Type, object>
Reads an object of the given type from a file.
serializeToFile Action<string, object>
Writes an object to a file.

Remarks

Call before the first LoadAssembly(Assembly). A cache file belongs to one build of an assembly, so a rebuilt assembly is read through reflection again. An unreadable file falls back to reflection as well. A process that can write to the directory decides which types the container creates, so keep the directory out of reach of untrusted users.

UseCustomTypeResolver(Func<string, Type>)

Replaces the resolver that turns a contract type name from a cache file into a type.

public void UseCustomTypeResolver(Func<string, Type> typeResolver)

Parameters

typeResolver Func<string, Type>
Resolver called with an assembly qualified type name. Default: Type.GetType(string).

Remarks

A resolver that returns null makes the container ignore the cache file and reflect over the assembly.

Events

ExportCollectionChanged

Occurs when exports are added or removed.

public EventHandler<ExportCollectionChangedEventArgs> ExportCollectionChanged

Event Type

EventHandler<ExportCollectionChangedEventArgs>