Task.WaitAll 方法

定义

等待所有提供的 Task 对象完成执行过程。Waits for all of the provided Task objects to complete execution.

重载

WaitAll(Task[])

等待提供的所有 Task 对象完成执行过程。Waits for all of the provided Task objects to complete execution.

WaitAll(Task[], Int32)

等待所有提供的 Task 在指定的毫秒数内完成执行。Waits for all of the provided Task objects to complete execution within a specified number of milliseconds.

WaitAll(Task[], CancellationToken)

等待提供的所有 Task 对象完成执行过程(除非取消等待)。Waits for all of the provided Task objects to complete execution unless the wait is cancelled.

WaitAll(Task[], TimeSpan)

等待所有提供的可取消 Task 对象在指定的时间间隔内完成执行。Waits for all of the provided cancellable Task objects to complete execution within a specified time interval.

WaitAll(Task[], Int32, CancellationToken)

等待提供的所有 Task 对象在指定的毫秒数内完成执行,或等到取消等待。Waits for all of the provided Task objects to complete execution within a specified number of milliseconds or until the wait is cancelled.

WaitAll(Task[])

等待提供的所有 Task 对象完成执行过程。Waits for all of the provided Task objects to complete execution.

public:
 static void WaitAll(... cli::array <System::Threading::Tasks::Task ^> ^ tasks);
public static void WaitAll (params System.Threading.Tasks.Task[] tasks);
static member WaitAll : System.Threading.Tasks.Task[] -> unit
Public Shared Sub WaitAll (ParamArray tasks As Task())

参数

tasks
Task[]

要等待的 Task 实例的数组。An array of Task instances on which to wait.

异常

tasks 中的一个或多个 Task 对象已释放。One or more of the Task objects in tasks has been disposed.

tasks 参数为 nullThe tasks argument is null.

tasks 参数包含一个 null 元素。The tasks argument contains a null element.

至少一个 Task 实例已取消。At least one of the Task instances was canceled. 如果任务取消,则 AggregateException 异常在其 InnerExceptions 集合中包含 OperationCanceledException 异常。If a task was canceled, the AggregateException exception contains an OperationCanceledException exception in its InnerExceptions collection.

-or- 在至少一个 Task 实例的执行过程中引发了异常。An exception was thrown during the execution of at least one of the Task instances.

示例

下面的示例启动了10个任务,其中每个任务都作为状态对象传递了一个索引。The following example starts 10 tasks, each of which is passed an index as a state object. 索引为2到5的任务引发异常。Tasks with an index from two to five throw exceptions. 调用 WaitAll 方法会将所有异常包装在 @no__t 1 对象中,并将其传播到调用线程。The call to the WaitAll method wraps all exceptions in an AggregateException object and propagates it to the calling thread.

using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;

class Example
{
    static void Main()
    {
        var tasks = new List<Task<int>>();
         
        // Define a delegate that prints and returns the system tick count
        Func<object, int> action = (object obj) =>
        {
            int i = (int)obj;

            // Make each thread sleep a different time in order to return a different tick count
            Thread.Sleep(i * 100);

            // The tasks that receive an argument between 2 and 5 throw exceptions
            if (2 <= i && i <= 5)
            {
                throw new InvalidOperationException("SIMULATED EXCEPTION");
            }

            int tickCount = Environment.TickCount;
            Console.WriteLine("Task={0}, i={1}, TickCount={2}, Thread={3}", Task.CurrentId, i, tickCount, Thread.CurrentThread.ManagedThreadId);

            return tickCount;
        };

        // Construct started tasks
        for (int i = 0; i < 10; i++)
        {
            int index = i;
            tasks.Add(Task<int>.Factory.StartNew(action, index));
        }

        try
        {
            // Wait for all the tasks to finish.
            Task.WaitAll(tasks.ToArray());

            // We should never get to this point
            Console.WriteLine("WaitAll() has not thrown exceptions. THIS WAS NOT EXPECTED.");
        }
        catch (AggregateException e)
        {
            Console.WriteLine("\nThe following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)");
            for (int j = 0; j < e.InnerExceptions.Count; j++)
            {
                Console.WriteLine("\n-------------------------------------------------\n{0}", e.InnerExceptions[j].ToString());
            }
        }
    }
}
// The example displays output like the following:
//     Task=1, i=0, TickCount=1203822250, Thread=3
//     Task=2, i=1, TickCount=1203822359, Thread=4
//     Task=7, i=6, TickCount=1203823484, Thread=3
//     Task=8, i=7, TickCount=1203823890, Thread=4
//     Task=9, i=8, TickCount=1203824296, Thread=3
//     Task=10, i=9, TickCount=1203824796, Thread=4
//     
//     The following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)
//     
//     -------------------------------------------------
//     System.InvalidOperationException: SIMULATED EXCEPTION
//        at Example.<Main>b__0(Object obj)
//        at System.Threading.Tasks.Task`1.InnerInvoke()
//        at System.Threading.Tasks.Task.Execute()
//     
//     -------------------------------------------------
//     System.InvalidOperationException: SIMULATED EXCEPTION
//        at Example.<Main>b__0(Object obj)
//        at System.Threading.Tasks.Task`1.InnerInvoke()
//        at System.Threading.Tasks.Task.Execute()
//     
//     -------------------------------------------------
//     System.InvalidOperationException: SIMULATED EXCEPTION
//        at Example.<Main>b__0(Object obj)
//        at System.Threading.Tasks.Task`1.InnerInvoke()
//        at System.Threading.Tasks.Task.Execute()
//     
//     -------------------------------------------------
//     System.InvalidOperationException: SIMULATED EXCEPTION
//        at Example.<Main>b__0(Object obj)
//        at System.Threading.Tasks.Task`1.InnerInvoke()
//        at System.Threading.Tasks.Task.Execute()
Imports System.Collections.Generic
Imports System.Threading
Imports System.Threading.Tasks

Module WaitAllDemo
    Sub Main()
        Dim tasks As New List(Of Task(Of Integer))()
        ' Define a delegate that prints and returns the system tick count
        Dim action As Func(Of Object, Integer) = Function(obj As Object)
                                                     Dim i As Integer = CInt(obj)

                                                     ' Make each thread sleep a different time in order to return a different tick count
                                                     Thread.Sleep(i * 100)

                                                     ' The tasks that receive an argument between 2 and 5 throw exceptions
                                                     If 2 <= i AndAlso i <= 5 Then
                                                         Throw New InvalidOperationException("SIMULATED EXCEPTION")
                                                     End If

                                                     Dim tickCount As Integer = Environment.TickCount
                                                     Console.WriteLine("Task={0}, i={1}, TickCount={2}, Thread={3}", Task.CurrentId, i, tickCount, Thread.CurrentThread.ManagedThreadId)

                                                     Return tickCount
                                                 End Function

        ' Construct started tasks
        For i As Integer = 0 To 9
            Dim index As Integer = i
            tasks.Add(Task(Of Integer).Factory.StartNew(action, index))
        Next

        Try
            ' Wait for all the tasks to finish.
            Task.WaitAll(tasks.ToArray())

            ' We should never get to this point
            Console.WriteLine("WaitAll() has not thrown exceptions. THIS WAS NOT EXPECTED.")
        Catch e As AggregateException
            Console.WriteLine(vbLf & "The following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)")
            For j As Integer = 0 To e.InnerExceptions.Count - 1
                Console.WriteLine(vbLf & "-------------------------------------------------" & vbLf & "{0}", e.InnerExceptions(j).ToString())
            Next
        End Try
    End Sub
End Module
' The example displays output like the following:
'     Task=1, i=0, TickCount=1203822250, Thread=3
'     Task=2, i=1, TickCount=1203822359, Thread=4
'     Task=7, i=6, TickCount=1203823484, Thread=3
'     Task=8, i=7, TickCount=1203823890, Thread=4
'     Task=9, i=8, TickCount=1203824296, Thread=3
'     Task=10, i=9, TickCount=1203824796, Thread=4
'     
'     The following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)
'     
'     -------------------------------------------------
'     System.InvalidOperationException: SIMULATED EXCEPTION
'        at Example.<Main>b__0(Object obj)
'        at System.Threading.Tasks.Task`1.InnerInvoke()
'        at System.Threading.Tasks.Task.Execute()
'     
'     -------------------------------------------------
'     System.InvalidOperationException: SIMULATED EXCEPTION
'        at Example.<Main>b__0(Object obj)
'        at System.Threading.Tasks.Task`1.InnerInvoke()
'        at System.Threading.Tasks.Task.Execute()
'     
'     -------------------------------------------------
'     System.InvalidOperationException: SIMULATED EXCEPTION
'        at Example.<Main>b__0(Object obj)
'        at System.Threading.Tasks.Task`1.InnerInvoke()
'        at System.Threading.Tasks.Task.Execute()
'     
'     -------------------------------------------------
'     System.InvalidOperationException: SIMULATED EXCEPTION
'        at Example.<Main>b__0(Object obj)
'        at System.Threading.Tasks.Task`1.InnerInvoke()
'        at System.Threading.Tasks.Task.Execute()

WaitAll(Task[], Int32)

等待所有提供的 Task 在指定的毫秒数内完成执行。Waits for all of the provided Task objects to complete execution within a specified number of milliseconds.

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, int millisecondsTimeout);
public static bool WaitAll (System.Threading.Tasks.Task[] tasks, int millisecondsTimeout);
static member WaitAll : System.Threading.Tasks.Task[] * int -> bool
Public Shared Function WaitAll (tasks As Task(), millisecondsTimeout As Integer) As Boolean

参数

tasks
Task[]

要等待的 Task 实例的数组。An array of Task instances on which to wait.

millisecondsTimeout
Int32

等待的毫秒数,或为 Infinite (-1),表示无限期等待。The number of milliseconds to wait, or Infinite (-1) to wait indefinitely.

返回

如果在分配的时间内所有 true 实例都已完成执行,则为 Task;否则为 falsetrue if all of the Task instances completed execution within the allotted time; otherwise, false.

异常

tasks 中的一个或多个 Task 对象已释放。One or more of the Task objects in tasks has been disposed.

tasks 参数为 nullThe tasks argument is null.

至少一个 Task 实例已取消。At least one of the Task instances was canceled. 如果任务已取消,则 AggregateException 在其 InnerExceptions 集合中包含 OperationCanceledExceptionIf a task was canceled, the AggregateException contains an OperationCanceledException in its InnerExceptions collection.

-or- 在至少一个 Task 实例的执行过程中引发了异常。An exception was thrown during the execution of at least one of the Task instances.

millisecondsTimeout 是一个非 -1 的负数,而 -1 表示无限期超时。millisecondsTimeout is a negative number other than -1, which represents an infinite time-out.

tasks 参数包含一个 null 元素。The tasks argument contains a null element.

WaitAll(Task[], CancellationToken)

等待提供的所有 Task 对象完成执行过程(除非取消等待)。Waits for all of the provided Task objects to complete execution unless the wait is cancelled.

public:
 static void WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, System::Threading::CancellationToken cancellationToken);
public static void WaitAll (System.Threading.Tasks.Task[] tasks, System.Threading.CancellationToken cancellationToken);
static member WaitAll : System.Threading.Tasks.Task[] * System.Threading.CancellationToken -> unit

参数

tasks
Task[]

要等待的 Task 实例的数组。An array of Task instances on which to wait.

cancellationToken
CancellationToken

等待任务完成期间要观察的 CancellationTokenA CancellationToken to observe while waiting for the tasks to complete.

异常

已取消 cancellationTokenThe cancellationToken was canceled.

tasks 参数为 nullThe tasks argument is null.

至少一个 Task 实例已取消。At least one of the Task instances was canceled. 如果任务已取消,则 AggregateException 在其 InnerExceptions 集合中包含 OperationCanceledExceptionIf a task was canceled, the AggregateException contains an OperationCanceledException in its InnerExceptions collection.

-or- 在至少一个 Task 实例的执行过程中引发了异常。An exception was thrown during the execution of at least one of the Task instances.

tasks 参数包含一个 null 元素。The tasks argument contains a null element.

tasks 中的一个或多个 Task 对象已释放。One or more of the Task objects in tasks has been disposed.

注解

@No__t-0 参数用于取消等待操作。The cancellationToken argument is used to cancel the wait operation. 取消任务是一项不同的操作,由上面所述的 AggregateException 发出信号。Cancellation of the tasks is a distinct operation, and is signaled by the AggregateException as noted above.

WaitAll(Task[], TimeSpan)

等待所有提供的可取消 Task 对象在指定的时间间隔内完成执行。Waits for all of the provided cancellable Task objects to complete execution within a specified time interval.

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, TimeSpan timeout);
public static bool WaitAll (System.Threading.Tasks.Task[] tasks, TimeSpan timeout);
static member WaitAll : System.Threading.Tasks.Task[] * TimeSpan -> bool
Public Shared Function WaitAll (tasks As Task(), timeout As TimeSpan) As Boolean

参数

tasks
Task[]

要等待的 Task 实例的数组。An array of Task instances on which to wait.

timeout
TimeSpan

表示等待毫秒数的 TimeSpan,或表示 -1 毫秒(无限期等待)的 TimeSpanA TimeSpan that represents the number of milliseconds to wait, or a TimeSpan that represents -1 milliseconds to wait indefinitely.

返回

如果在分配的时间内所有 true 实例都已完成执行,则为 Task;否则为 falsetrue if all of the Task instances completed execution within the allotted time; otherwise, false.

异常

tasks 中的一个或多个 Task 对象已释放。One or more of the Task objects in tasks has been disposed.

tasks 参数为 nullThe tasks argument is null.

至少一个 Task 实例已取消。At least one of the Task instances was canceled. 如果任务已取消,则 AggregateException 在其 InnerExceptions 集合中包含 OperationCanceledExceptionIf a task was canceled, the AggregateException contains an OperationCanceledException in its InnerExceptions collection.

- 或 --or- 在至少一个 Task 实例的执行过程中引发了异常。An exception was thrown during the execution of at least one of the Task instances.

timeout 为 -1 毫秒以外的负数,表示无限期超时。timeout is a negative number other than -1 milliseconds, which represents an infinite time-out. -or- timeout 大于 MaxValuetimeout is greater than MaxValue.

tasks 参数包含一个 null 元素。The tasks argument contains a null element.

WaitAll(Task[], Int32, CancellationToken)

等待提供的所有 Task 对象在指定的毫秒数内完成执行,或等到取消等待。Waits for all of the provided Task objects to complete execution within a specified number of milliseconds or until the wait is cancelled.

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, int millisecondsTimeout, System::Threading::CancellationToken cancellationToken);
public static bool WaitAll (System.Threading.Tasks.Task[] tasks, int millisecondsTimeout, System.Threading.CancellationToken cancellationToken);
static member WaitAll : System.Threading.Tasks.Task[] * int * System.Threading.CancellationToken -> bool

参数

tasks
Task[]

要等待的 Task 实例的数组。An array of Task instances on which to wait.

millisecondsTimeout
Int32

等待的毫秒数,或为 Infinite (-1),表示无限期等待。The number of milliseconds to wait, or Infinite (-1) to wait indefinitely.

cancellationToken
CancellationToken

等待任务完成期间要观察的 CancellationTokenA CancellationToken to observe while waiting for the tasks to complete.

返回

如果在分配的时间内所有 true 实例都已完成执行,则为 Task;否则为 falsetrue if all of the Task instances completed execution within the allotted time; otherwise, false.

异常

tasks 中的一个或多个 Task 对象已释放。One or more of the Task objects in tasks has been disposed.

tasks 参数为 nullThe tasks argument is null.

至少一个 Task 实例已取消。At least one of the Task instances was canceled. 如果任务已取消,则 AggregateException 在其 InnerExceptions 集合中包含 OperationCanceledExceptionIf a task was canceled, the AggregateException contains an OperationCanceledException in its InnerExceptions collection.

- 或 --or- 在至少一个 Task 实例的执行过程中引发了异常。An exception was thrown during the execution of at least one of the Task instances.

millisecondsTimeout 是一个非 -1 的负数,而 -1 表示无限期超时。millisecondsTimeout is a negative number other than -1, which represents an infinite time-out.

tasks 参数包含一个 null 元素。The tasks argument contains a null element.

已取消 cancellationTokenThe cancellationToken was canceled.

注解

@No__t-0 参数用于取消等待操作。The cancellationToken argument is used to cancel the wait operation. 取消任务是一项不同的操作,由上面所述的 AggregateException 发出信号。Cancellation of the tasks is a distinct operation, and is signaled by the AggregateException noted above.

适用于