Task.WaitAll 方法

定義

命名空間:

System.Threading.Tasks

組件:

System.Runtime.dll

等候所有提供 Task 物件完成執行。

多載

WaitAll(Task[], Int32, CancellationToken)	等候所有提供 Task 物件在指定的毫秒數內完成執行，或等到等候取消為止。
WaitAll(Task[])	等候所有提供 Task 物件完成執行。
WaitAll(Task[], Int32)	等候所有提供的 Task 物件在指定的毫秒數內完成執行。
WaitAll(Task[], CancellationToken)	等候所有提供 Task 物件完成執行，除非取消等候。
WaitAll(Task[], TimeSpan)	等候所有提供的可取消 Task 物件在指定的時間間隔內完成執行。

WaitAll(Task[], Int32, CancellationToken)

來源:

Task.cs

等候所有提供 Task 物件在指定的毫秒數內完成執行，或等到等候取消為止。

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, int millisecondsTimeout, System::Threading::CancellationToken cancellationToken);

[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public static bool WaitAll (System.Threading.Tasks.Task[] tasks, int millisecondsTimeout, System.Threading.CancellationToken cancellationToken);

[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
static member WaitAll : System.Threading.Tasks.Task[] * int * System.Threading.CancellationToken -> bool

Public Shared Function WaitAll (tasks As Task(), millisecondsTimeout As Integer, cancellationToken As CancellationToken) As Boolean

參數

tasks

Task[]

要等候 Task 實例的陣列。

millisecondsTimeout

Int32

等候的毫秒數，或 Infinite （-1） 無限期等候。

cancellationToken

CancellationToken

等候工作完成時要觀察的 CancellationToken。

傳回

Boolean

如果所有 Task 實例在分配的時間內完成執行，true;否則，false。

屬性

UnsupportedOSPlatformAttribute

例外狀況

ObjectDisposedException

已處置 tasks 中的一或多個 Task 物件。

ArgumentNullException

tasks 自變數 null。

AggregateException

至少已取消其中一個 Task 實例。 如果工作已取消，AggregateException 會在其 InnerExceptions 集合中包含 OperationCanceledException。

-或-

執行至少一個 Task 實例時擲回例外狀況。

ArgumentOutOfRangeException

millisecondsTimeout 是 -1 以外的負數，代表無限逾時。

ArgumentException

tasks 自變數包含 null 元素。

OperationCanceledException

cancellationToken 已取消。

備註

cancellationToken 自變數可用來取消等候作業。 取消工作是一項不同的作業，而且會由上述 AggregateException 發出訊號。

WaitAll(Task[])

來源:

Task.cs

等候所有提供 Task 物件完成執行。

public:
 static void WaitAll(... cli::array <System::Threading::Tasks::Task ^> ^ tasks);

[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public static void WaitAll (params System.Threading.Tasks.Task[] tasks);

[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
static member WaitAll : System.Threading.Tasks.Task[] -> unit

Public Shared Sub WaitAll (ParamArray tasks As Task())

參數

tasks

Task[]

要等候 Task 實例的陣列。

屬性

UnsupportedOSPlatformAttribute

例外狀況

ObjectDisposedException

已處置 tasks 中的一或多個 Task 物件。

ArgumentNullException

tasks 自變數 null。

ArgumentException

tasks 自變數包含 null 元素。

AggregateException

至少已取消其中一個 Task 實例。 如果工作已取消，AggregateException 例外狀況會在其 InnerExceptions 集合中包含 OperationCanceledException 例外狀況。

-或-

執行至少一個 Task 實例時擲回例外狀況。

範例

下列範例會啟動 10 個工作，每個工作都會以狀態物件的形式傳遞索引。 索引從 2 到 5 個的工作會擲回例外狀況。 呼叫 WaitAll 方法會將所有例外狀況包裝在 AggregateException 物件中，並將它傳播至呼叫線程。

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()

open System
open System.Threading
open System.Threading.Tasks

// Define a delegate that prints and returns the system tick count
let action =
    fun (obj: obj) ->
        let i = obj :?> int

        // 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 then
            raise (InvalidOperationException "SIMULATED EXCEPTION")


        let tickCount = Environment.TickCount
        printfn $"Task={Task.CurrentId}, i={i}, TickCount={tickCount}, Thread={Thread.CurrentThread.ManagedThreadId}"
        tickCount

// Construct started tasks
let tasks =
    [| for i = 0 to 9 do
           Task<int>.Factory.StartNew (action, i) |]

try

    // Wait for all the tasks to finish.
    Seq.cast tasks |> Seq.toArray |> Task.WaitAll

    // We should never get to this point
    printfn "WaitAll() has not thrown exceptions. THIS WAS NOT EXPECTED."

with :? AggregateException as e ->
    printfn "\nThe following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)"

    for ex in e.InnerExceptions do
        printfn $"\n-------------------------------------------------\n{ex}"

// 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)

來源:

Task.cs

等候所有提供的 Task 物件在指定的毫秒數內完成執行。

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, int millisecondsTimeout);

[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public static bool WaitAll (System.Threading.Tasks.Task[] tasks, int millisecondsTimeout);

[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
static member WaitAll : System.Threading.Tasks.Task[] * int -> bool

Public Shared Function WaitAll (tasks As Task(), millisecondsTimeout As Integer) As Boolean

參數

tasks

Task[]

要等候 Task 實例的陣列。

millisecondsTimeout

Int32

等候的毫秒數，或 Infinite （-1） 無限期等候。

傳回

Boolean

如果所有 Task 實例在分配的時間內完成執行，true;否則，false。

屬性

UnsupportedOSPlatformAttribute

例外狀況

ObjectDisposedException

已處置 tasks 中的一或多個 Task 物件。

ArgumentNullException

tasks 自變數 null。

AggregateException

至少已取消其中一個 Task 實例。 如果工作已取消，AggregateException 會在其 InnerExceptions 集合中包含 OperationCanceledException。

-或-

執行至少一個 Task 實例時擲回例外狀況。

ArgumentOutOfRangeException

millisecondsTimeout 是 -1 以外的負數，代表無限逾時。

ArgumentException

tasks 自變數包含 null 元素。

WaitAll(Task[], CancellationToken)

來源:

Task.cs

等候所有提供 Task 物件完成執行，除非取消等候。

public:
 static void WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, System::Threading::CancellationToken cancellationToken);

[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public static void WaitAll (System.Threading.Tasks.Task[] tasks, System.Threading.CancellationToken cancellationToken);

[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
static member WaitAll : System.Threading.Tasks.Task[] * System.Threading.CancellationToken -> unit

Public Shared Sub WaitAll (tasks As Task(), cancellationToken As CancellationToken)

參數

tasks

Task[]

要等候 Task 實例的陣列。

cancellationToken

CancellationToken

等候工作完成時要觀察的 CancellationToken。

屬性

UnsupportedOSPlatformAttribute

例外狀況

OperationCanceledException

cancellationToken 已取消。

ArgumentNullException

tasks 自變數 null。

AggregateException

至少已取消其中一個 Task 實例。 如果工作已取消，AggregateException 會在其 InnerExceptions 集合中包含 OperationCanceledException。

-或-

執行至少一個 Task 實例時擲回例外狀況。

ArgumentException

tasks 自變數包含 null 元素。

ObjectDisposedException

已處置 tasks 中的一或多個 Task 物件。

備註

cancellationToken 自變數可用來取消等候作業。 取消工作是不同的作業，由 AggregateException 發出訊號，如上所述。

WaitAll(Task[], TimeSpan)

來源:

Task.cs

等候所有提供的可取消 Task 物件在指定的時間間隔內完成執行。

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, TimeSpan timeout);

[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public static bool WaitAll (System.Threading.Tasks.Task[] tasks, TimeSpan timeout);

[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
static member WaitAll : System.Threading.Tasks.Task[] * TimeSpan -> bool

Public Shared Function WaitAll (tasks As Task(), timeout As TimeSpan) As Boolean

參數

tasks

Task[]

要等候 Task 實例的陣列。

timeout

TimeSpan

TimeSpan，表示要等候的毫秒數，或代表無限期等候 -1 毫秒的 TimeSpan。

傳回

Boolean

如果所有 Task 實例在分配的時間內完成執行，true;否則，false。

屬性

UnsupportedOSPlatformAttribute

例外狀況

ObjectDisposedException

已處置 tasks 中的一或多個 Task 物件。

ArgumentNullException

tasks 自變數 null。

AggregateException

至少已取消其中一個 Task 實例。 如果工作已取消，AggregateException 會在其 InnerExceptions 集合中包含 OperationCanceledException。

-或-

執行至少一個 Task 實例時擲回例外狀況。

ArgumentOutOfRangeException

timeout 是非 -1 毫秒以外的負數，代表無限逾時。

-或-

timeout 大於 Int32.MaxValue。

ArgumentException

tasks 自變數包含 null 元素。