Start(IEnumerable<Func<INotifyCompleted>>,Action<CoroutineOperation>) Method

Start serial execution of multiple asynchronous actions.

Syntax

Visual Basic
C#

'Declaration
 
Public Overloads Shared Function Start( _
   ByVal asyncFns As IEnumerable(Of Func(Of INotifyCompleted)), _
   Optional ByVal completedHandler As Action(Of CoroutineOperation) _
) As CoroutineOperation

'Usage
 
Dim asyncFns As IEnumerable(Of Func(Of INotifyCompleted))
Dim completedHandler As Action(Of CoroutineOperation)
Dim value As CoroutineOperation
 
value = Coroutine.Start(asyncFns, completedHandler)

public static CoroutineOperation Start( 
   IEnumerable<Func<INotifyCompleted>> asyncFns,
   Action<CoroutineOperation> completedHandler
)

Parameters

asyncFns: List of asynchronous functions
completedHandler: Optional completion handle

Return Value

A CoroutineOperation representing this operation

Remarks

Used to start serial execution of a list of asynchronous actions. Instead of passing an iterator block, pass an IEnumerable of the asynchronous functions to be executed. Asynchronous functions in the list will be executed serially.

This overload of the Start method is useful in Visual Basic, where iterators are not supported.

Example

C#
Visual Basic

public void CoroutineSample3() {
  Coroutine.Start(Sample3Actions(_entityManager), (op) => {
    MessageBox.Show(op.Result.ToString());
  });
}

private IEnumerable<Func<INotifyCompleted>> Sample3Actions(DomainModelEntityManager mgr) {
  // Not an iterator block - this returns a list of async actions

  yield return () => mgr.Customers.ExecuteAsync();
  yield return () => mgr.Employees.ExecuteAsync();
  yield return () => Coroutine.Return("all done");
}

Public Sub CoroutineSample3()
    Coroutine.Start(Sample3Actions(Manager),
        Sub(op As CoroutineOperation)
            MessageBox.Show(op.Result.ToString())
        End Sub)
End Sub

Private Function Sample3Actions(ByVal mgr As NorthwindIBEntities) As IEnumerable(Of Func(Of INotifyCompleted))
    ' Setup of the list of async functions for the Coroutine to execute serially.
    Dim operationList = New List(Of Func(Of INotifyCompleted))

    Dim f1 As Func(Of INotifyCompleted) = Function() mgr.Customers.ExecuteAsync()
    operationList.Add(f1)

    Dim f2 As Func(Of INotifyCompleted) = Function() mgr.Employees.ExecuteAsync()
    operationList.Add(f2)

    Dim f3 As Func(Of INotifyCompleted) = Function() Coroutine.Return("all done")
    operationList.Add(f3)

    Return operationList
End Function

Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

Coroutine Class
Coroutine Members
Overload List