本文整理匯總了VB.NET中System.Threading.Tasks.TaskExtensions.Unwrap方法的典型用法代碼示例。如果您正苦於以下問題：VB.NET TaskExtensions.Unwrap方法的具體用法？VB.NET TaskExtensions.Unwrap怎麽用？VB.NET TaskExtensions.Unwrap使用的例子？那麽, 這裏精選的方法代碼示例或許可以為您提供幫助。
在下文中一共展示了TaskExtensions.Unwrap方法的1個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的VB.NET代碼示例。
示例1: UnwrapDemo
' 導入命名空間
Imports System.Threading
Imports System.Threading.Tasks
Module UnwrapDemo
' Demonstrated features:
' Task.Unwrap()
' Task.Factory.StartNew()
' Task.ContinueWith()
' Expected results:
' Indicates that continuation chains can be set up virtually instantaneously using Unwrap(), and then left to run on their own.
' The results of the RemoteIncrement(0) chain and the RemoteIncrement(4) chain may be intermixed with each other.
' The results of the sequence that starts with RemoteIncrement(4) are in strict order.
' Documentation:
' http://msdn.microsoft.com/library/dd781129(VS.100).aspx
' More information:
' http://blogs.msdn.com/pfxteam/archive/2009/11/04/9917581.aspx
' Other notes:
' The combination of Task<T>, ContinueWith() and Unwrap() can be particularly useful for setting up a chain of long-running
' tasks where each task uses the results of its predecessor.
Sub Main()
' Invoking individual tasks is straightforward
Dim t1 As Task(Of Integer) = RemoteIncrement(0)
Console.WriteLine("Started RemoteIncrement(0)")
' Chain together the results of (simulated) remote operations.
' The use of Unwrap() instead of .Result below prevents this thread from blocking while setting up this continuation chain.
' RemoteIncrement() returns Task<int> so no unwrapping is needed for the first continuation.
' ContinueWith() here returns Task<Task<int>>. Therefore unwrapping is needed.
' and on it goes...
Dim t2 As Task(Of Integer) = RemoteIncrement(4).ContinueWith(Function(t) RemoteIncrement(t.Result)).Unwrap().ContinueWith(Function(t) RemoteIncrement(t.Result)).Unwrap().ContinueWith(Function(t) RemoteIncrement(t.Result)).Unwrap()
Console.WriteLine("Started RemoteIncrement(...(RemoteIncrement(RemoteIncrement(4))...)")
Try
t1.Wait()
Console.WriteLine("Finished RemoteIncrement(0)" & vbLf)
t2.Wait()
Console.WriteLine("Finished RemoteIncrement(...(RemoteIncrement(RemoteIncrement(4))...)")
Catch e As AggregateException
Console.WriteLine("A task has thrown the following (unexpected) exception:" & vbLf & "{0}", e)
End Try
End Sub
' This method represents a remote API.
Function RemoteIncrement(ByVal n As Integer) As Task(Of Integer)
Return Task(Of Integer).Factory.StartNew(Function(obj)
' Simulate a slow operation
Thread.Sleep(1 * 1000)
Dim x As Integer = CInt(obj)
Console.WriteLine("Thread={0}, Next={1}", Thread.CurrentThread.ManagedThreadId, System.Threading.Interlocked.Increment(x))
Return x
End Function, n)
End Function
End Module