WorkflowRuntime.AddService Method (System.Workflow.Runtime)

.NET Framework Class Library

WorkflowRuntime..::.AddService Method

Adds the specified service to the workflow runtime engine.

Namespace: System.Workflow.Runtime
Assembly: System.Workflow.Runtime (in System.Workflow.Runtime.dll)

Syntax

Visual Basic (Declaration)

Public Sub AddService ( _
    service As Object _
)

Visual Basic (Usage)

Dim instance As WorkflowRuntime
Dim service As Object

instance.AddService(service)

public void AddService(
    Object service
)

Visual C++

public:
void AddService(
    Object^ service
)

JScript

public function AddService(
    service : Object
)

Parameters

service: Type: System..::.Object
An object that represents the service to add.

Exceptions

Exception	Condition
ArgumentNullException	service is a null reference (Nothing in Visual Basic)
ObjectDisposedException	The WorkflowRuntime is disposed.
InvalidOperationException	service is already registered with the workflow runtime engine. -or- service is a core service and the workflow runtime engine is already running (IsStarted is true).

Exception

Condition

ArgumentNullException

service is a null reference (Nothing in Visual Basic)

ObjectDisposedException

The WorkflowRuntime is disposed.

InvalidOperationException

service is already registered with the workflow runtime engine.

-or-

service is a core service and the workflow runtime engine is already running (IsStarted is true).

Remarks

You can configure the workflow runtime engine by adding core services. Core services are those that derive from any of the following service base classes: the WorkflowSchedulerService class, the WorkflowCommitWorkBatchService class, the WorkflowPersistenceService class, and the TrackingService class. Core services can only be added when the workflow runtime engine is not running; that is, when IsStarted is false. The WorkflowRuntime can also be used as a storage container for other services that may be used by other workflows or by applications running on a host. If you add a non-core service that derives from the WorkflowRuntimeService class after the workflow runtime engine has been started, AddService will call the Start method implemented by that service.

Note:
AddService enforces the restriction that no two services of the same Type may be added to the WorkflowRuntime; however, you can add multiple services that derive from the same base class. There can be only one service derived from each of the following service base classes in the WorkflowRuntime: the WorkflowSchedulerService class, the WorkflowCommitWorkBatchService class, and the WorkflowPersistenceService class. If you add multiple services derived from one of these classes, for example two persistence services, StartRuntime will throw an InvalidOperationException.

Note:

AddService enforces the restriction that no two services of the same Type may be added to the WorkflowRuntime; however, you can add multiple services that derive from the same base class. There can be only one service derived from each of the following service base classes in the WorkflowRuntime: the WorkflowSchedulerService class, the WorkflowCommitWorkBatchService class, and the WorkflowPersistenceService class. If you add multiple services derived from one of these classes, for example two persistence services, StartRuntime will throw an InvalidOperationException.

Examples

The following code example demonstrates how you can use WorkflowRuntime functionality from a workflow host. It provides example of how to use the AddService method to add an ExternalDataExchangeService and SqlWorkflowPersistenceService to the workflow runtime engine.

This code example is part of the Cancelling a Workflow SDK sample from the Program.cs file. For more information, see Cancelling a Workflow.

Visual Basic

Shared Sub Main()
    Dim connectionString As String = "Initial Catalog=SqlPersistenceService;Data Source=localhost;Integrated Security=SSPI;"
    Using workflowRuntime As New WorkflowRuntime()
        Dim dataService As New ExternalDataExchangeService()
        workflowRuntime.AddService(dataService)
        dataService.AddService(expenseService)

        workflowRuntime.AddService(New SqlWorkflowPersistenceService(connectionString))


        AddHandler workflowRuntime.WorkflowCompleted, AddressOf OnWorkflowCompleted
        AddHandler workflowRuntime.WorkflowTerminated, AddressOf OnWorkflowTerminated
        AddHandler workflowRuntime.WorkflowIdled, AddressOf OnWorkflowIdled
        AddHandler workflowRuntime.WorkflowAborted, AddressOf OnWorkflowAborted


        Dim workflowInstance As WorkflowInstance
        workflowInstance = workflowRuntime.CreateWorkflow(GetType(SampleWorkflow))
        workflowInstance.Start()

        waitHandle.WaitOne()

        workflowRuntime.StopRuntime()
    End Using
End Sub

static void Main()
{
    string connectionString = "Initial Catalog=SqlPersistenceService;Data Source=localhost;Integrated Security=SSPI;";

    using (WorkflowRuntime workflowRuntime = new WorkflowRuntime())
    {
        ExternalDataExchangeService dataService = new ExternalDataExchangeService();
        workflowRuntime.AddService(dataService);
        dataService.AddService(expenseService);

        workflowRuntime.AddService(new SqlWorkflowPersistenceService(connectionString));
        workflowRuntime.StartRuntime();

        workflowRuntime.WorkflowCompleted += OnWorkflowCompleted;
        workflowRuntime.WorkflowTerminated += OnWorkflowTerminated;
        workflowRuntime.WorkflowIdled += OnWorkflowIdled;
        workflowRuntime.WorkflowAborted += OnWorkflowAborted;

        Type type = typeof(SampleWorkflow1);
        WorkflowInstance workflowInstance = workflowRuntime.CreateWorkflow(type);
        workflowInstance.Start();

        waitHandle.WaitOne();

        workflowRuntime.StopRuntime();
    }
}

.NET Framework Security

Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see Using Libraries from Partially Trusted Code.

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information

.NET Framework

Supported in: 3.5, 3.0

Reference

WorkflowRuntime Class

WorkflowRuntime Members

System.Workflow.Runtime Namespace

Other Resources

Cancelling a Workflow