ServiceCreatorCallback Delegate

Reference

Definition

Namespace:: System.ComponentModel.Design

Assembly:: System.ComponentModel.TypeConverter.dll

Assembly:: System.dll

Assembly:: netstandard.dll

Important

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Provides a callback mechanism that can create an instance of a service on demand.

public delegate System::Object ^ ServiceCreatorCallback(IServiceContainer ^ container, Type ^ serviceType);

public delegate object ServiceCreatorCallback(IServiceContainer container, Type serviceType);

public delegate object? ServiceCreatorCallback(IServiceContainer container, Type serviceType);

[System.Runtime.InteropServices.ComVisible(true)]
public delegate object ServiceCreatorCallback(IServiceContainer container, Type serviceType);

type ServiceCreatorCallback = delegate of IServiceContainer * Type -> obj

[<System.Runtime.InteropServices.ComVisible(true)>]
type ServiceCreatorCallback = delegate of IServiceContainer * Type -> obj

Public Delegate Function ServiceCreatorCallback(container As IServiceContainer, serviceType As Type) As Object

Parameters

container: IServiceContainer

The service container that requested the creation of the service.

serviceType: Type

The type of service to create.

Return Value

Object

The service specified by serviceType, or null if the service could not be created.

Attributes: ComVisibleAttribute

Examples

The following code example shows how to publish a service using a callback function.

// The following code shows how to publish a service using a callback function.
// Creates a service creator callback.
ServiceCreatorCallback^ callback1 =
   gcnew ServiceCreatorCallback( this, &Sample::myCallBackMethod );

// Adds the service using its type and the service creator callback.
serviceContainer->AddService( myService::typeid, callback1 );

// The following code shows how to publish a service using a callback function.

// Creates a service creator callback.
ServiceCreatorCallback callback1 = 
new ServiceCreatorCallback(myCallBackMethod);

// Adds the service using its type and the service creator callback.
serviceContainer.AddService(typeof(myService), callback1);

' The following code shows how to publish a service using a callback function.

' Creates a service creator callback.
Dim callback1 As New ServiceCreatorCallback _
(AddressOf myCallBackMethod)
       
' Adds the service using its type and the service creator.
serviceContainer.AddService(GetType(myService), callback1)

Remarks

ServiceCreatorCallback provides a mechanism to publish services that you can request to have created when needed, rather than the service being created immediately when the designer loads. You can use a callback function if the service is not essential and may not be used. A service published by using a ServiceCreatorCallback does not use as many additional resources if it is not requested and created. To use a callback function to publish your service, pass a ServiceCreatorCallback to the AddService method of an IServiceContainer.

Extension Methods

GetMethodInfo(Delegate)

Gets an object that represents the method represented by the specified delegate.

Applies to

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