TaskFactory.StartNew 方法

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
 System::Threading::Tasks::Task ^ StartNew(Action<System::Object ^> ^ action, System::Object ^ state, System::Threading::CancellationToken cancellationToken, System::Threading::Tasks::TaskCreationOptions creationOptions, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task StartNew(Action<object> action, object state, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskCreationOptions creationOptions, System.Threading.Tasks.TaskScheduler scheduler);

public System.Threading.Tasks.Task StartNew(Action<object?> action, object? state, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskCreationOptions creationOptions, System.Threading.Tasks.TaskScheduler scheduler);

member this.StartNew : Action<obj> * obj * System.Threading.CancellationToken * System.Threading.Tasks.TaskCreationOptions * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task

Public Function StartNew (action As Action(Of Object), state As Object, cancellationToken As CancellationToken, creationOptions As TaskCreationOptions, scheduler As TaskScheduler) As Task

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其中一個建構子建立任務，然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
 System::Threading::Tasks::Task ^ StartNew(Action ^ action, System::Threading::CancellationToken cancellationToken, System::Threading::Tasks::TaskCreationOptions creationOptions, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task StartNew(Action action, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskCreationOptions creationOptions, System.Threading.Tasks.TaskScheduler scheduler);

member this.StartNew : Action * System.Threading.CancellationToken * System.Threading.Tasks.TaskCreationOptions * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task

Public Function StartNew (action As Action, cancellationToken As CancellationToken, creationOptions As TaskCreationOptions, scheduler As TaskScheduler) As Task

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其中一個建構子建立任務，然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
 System::Threading::Tasks::Task ^ StartNew(Action<System::Object ^> ^ action, System::Object ^ state, System::Threading::Tasks::TaskCreationOptions creationOptions);

public System.Threading.Tasks.Task StartNew(Action<object> action, object state, System.Threading.Tasks.TaskCreationOptions creationOptions);

public System.Threading.Tasks.Task StartNew(Action<object?> action, object? state, System.Threading.Tasks.TaskCreationOptions creationOptions);

member this.StartNew : Action<obj> * obj * System.Threading.Tasks.TaskCreationOptions -> System.Threading.Tasks.Task

Public Function StartNew (action As Action(Of Object), state As Object, creationOptions As TaskCreationOptions) As Task

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其中一個建構子建立任務，然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
 System::Threading::Tasks::Task ^ StartNew(Action<System::Object ^> ^ action, System::Object ^ state, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task StartNew(Action<object> action, object state, System.Threading.CancellationToken cancellationToken);

public System.Threading.Tasks.Task StartNew(Action<object?> action, object? state, System.Threading.CancellationToken cancellationToken);

member this.StartNew : Action<obj> * obj * System.Threading.CancellationToken -> System.Threading.Tasks.Task

Public Function StartNew (action As Action(Of Object), state As Object, cancellationToken As CancellationToken) As Task

參數

傳回

開始的任務。

例外狀況

範例

以下範例定義了一個由六字母組成的詞彙陣列。 每個字會交給 Action<T> 一位代表，代表會將字詞打亂並顯示原始字及其打亂後的版本。

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

public class Example
{
   public static void Main()
   {
      CancellationTokenSource cts = new CancellationTokenSource();
      CancellationToken token = cts.Token;
      var tasks = new List<Task>();
      Random rnd = new Random();
      Object lockObj = new Object();
      String[] words6 = { "reason", "editor", "rioter", "rental",
                          "senior", "regain", "ordain", "rained" };

      foreach (var word6 in words6)
         tasks.Add(Task.Factory.StartNew( (word) => { Char[] chars = word.ToString().ToCharArray();
                                                      double[] order = new double[chars.Length];
                                                      token.ThrowIfCancellationRequested();
                                                      bool wasZero = false;
                                                      lock (lockObj) {
                                                         for (int ctr = 0; ctr < order.Length; ctr++) {
                                                             order[ctr] = rnd.NextDouble();
                                                             if (order[ctr] == 0) {
                                                                if (!wasZero) {
                                                                   wasZero = true;
                                                                }
                                                                else {
                                                                   cts.Cancel();
                                                                }
                                                             }
                                                         }
                                                      }
                                                      token.ThrowIfCancellationRequested();
                                                      Array.Sort(order, chars);
                                                      Console.WriteLine("{0} --> {1}", word,
                                                                        new String(chars));
                                                    }, word6, token));

      try {
         Task.WaitAll(tasks.ToArray());
      }
      catch (AggregateException e) {
         foreach (var ie in e.InnerExceptions) {
            if (ie is OperationCanceledException) {
               Console.WriteLine("The word scrambling operation has been cancelled.");
               break;
            }
            else {
               Console.WriteLine(ie.GetType().Name + ": " + ie.Message);
            }
         }
      }
      finally {
         cts.Dispose();
      }
   }
}
// The example displays output like the following:
//    regain --> irnaeg
//    ordain --> rioadn
//    reason --> soearn
//    rained --> rinade
//    rioter --> itrore
//    senior --> norise
//    rental --> atnerl
//    editor --> oteird

Imports System.Collections.Generic
Imports System.Threading
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim cts As New CancellationTokenSource()
      Dim token As CancellationToken = cts.Token
      Dim tasks As New List(Of Task)()
      Dim rnd As New Random()
      Dim lockObj As New Object()
      Dim words6() As String = { "reason", "editor", "rioter", "rental",
                                 "senior", "regain", "ordain", "rained" }

      For Each word6 in words6
         tasks.Add(Task.Factory.StartNew( Sub(word)
                                              Dim chars() As Char = word.ToString().ToCharArray()
                                              Dim order(chars.Length - 1) As Double
                                              Dim wasZero As Boolean = False
                                              SyncLock lockObj
                                                 For ctr As Integer = 0 To order.Length - 1
                                                    order(ctr) = rnd.NextDouble()
                                                    If order(ctr) = 0 Then
                                                       If Not wasZero Then
                                                          wasZero = True
                                                       Else
                                                          cts.Cancel()
                                                       End If
                                                    End If
                                                 Next
                                              End SyncLock
                                              token.ThrowIfCancellationRequested()
                                              Array.Sort(order, chars)
                                              Console.WriteLine("{0} --> {1}", word,
                                                                new String(chars))
                                          End Sub, word6))
      Next
      Try
         Task.WaitAll(tasks.ToArray())
      Catch e As AggregateException
         For Each ie In e.InnerExceptions
            If TypeOf ie Is OperationCanceledException
               Console.WriteLine("The word scrambling operation has been cancelled.")
               Exit For
            Else
               Console.WriteLine(ie.GetType().Name + ": " + ie.Message)
            End If
         Next
      Finally
         cts.Dispose()
      End Try
   End Sub
End Module
' The example displays output like the following:
'       regain --> irnaeg
'       ordain --> rioadn
'       reason --> soearn
'       rained --> rinade
'       rioter --> itrore
'       senior --> norise
'       rental --> atnerl
'       editor --> oteird

請注意，範例初始化了一個隨機數產生器，該生成器受到鎖的保護。 關於鎖的需求，請參見課程主題中的 Random 「The System.Random class and thread safety」。 為了處理隨機數產生器可能損壞的可能性，會將一個消去標記傳遞給任務。 若兩個隨機數為零，該方法假設隨機數產生器已損壞，並設定消去標記。 在排序 chars 包含字中六個字元的陣列之前，若標記已被取消，方法會呼叫 CancellationToken.ThrowIfCancellationRequested 該方法拋出 an OperationCanceledException 。

備註

呼叫 StartNew 在功能上等同於使用其中一個建構子建立任務，然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
 System::Threading::Tasks::Task ^ StartNew(Action ^ action, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task StartNew(Action action, System.Threading.CancellationToken cancellationToken);

member this.StartNew : Action * System.Threading.CancellationToken -> System.Threading.Tasks.Task

Public Function StartNew (action As Action, cancellationToken As CancellationToken) As Task

參數

傳回

開始的任務。

例外狀況

範例

以下範例呼叫 StartNew(Action, CancellationToken) 該方法來建立一個任務，會迭代 C：\Windows\System32 目錄中的檔案。 lambda 運算 Parallel.ForEach 式呼叫方法，將每個檔案的資訊加入物件 List<T> 。 迴圈呼叫的每個分離巢狀任務 Parallel.ForEach 都會檢查消去標記的狀態，若請求取消，則呼叫該 CancellationToken.ThrowIfCancellationRequested 方法。 當呼叫執行緒呼叫該CancellationToken.ThrowIfCancellationRequested方法時，該OperationCanceledException方法會拋出catch一個例外，該異常會被Task.Wait區塊處理。

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

public class Example
{
   public static void Main()
   {
      var tokenSource = new CancellationTokenSource();
      var token = tokenSource.Token;
      var files = new List<Tuple<string, string, long, DateTime>>();

      var t = Task.Factory.StartNew( () => { string dir = "C:\\Windows\\System32\\";
                                object obj = new Object();
                                if (Directory.Exists(dir)) {
                                   Parallel.ForEach(Directory.GetFiles(dir),
                                   f => {
                                           if (token.IsCancellationRequested)
                                              token.ThrowIfCancellationRequested();
                                           var fi = new FileInfo(f);
                                           lock(obj) {
                                              files.Add(Tuple.Create(fi.Name, fi.DirectoryName, fi.Length, fi.LastWriteTimeUtc));          
                                           }
                                      });
                                 }
                              }
                        , token);
      tokenSource.Cancel();
      try {
         t.Wait(); 
         Console.WriteLine("Retrieved information for {0} files.", files.Count);
      }
      catch (AggregateException e) {
         Console.WriteLine("Exception messages:");
         foreach (var ie in e.InnerExceptions)
            Console.WriteLine("   {0}: {1}", ie.GetType().Name, ie.Message);

         Console.WriteLine("\nTask status: {0}", t.Status);       
      }
      finally {
         tokenSource.Dispose();
      }
   }
}
// The example displays the following output:
//       Exception messages:
//          TaskCanceledException: A task was canceled.
//       
//       Task status: Canceled

Imports System.Collections.Generic
Imports System.IO
Imports System.Threading
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim tokenSource As New CancellationTokenSource()
      Dim token As CancellationToken = tokenSource.Token
      Dim files As New List(Of Tuple(Of String, String, Long, Date))()

      Dim t As Task = Task.Factory.StartNew( Sub()
                                   Dim dir As String = "C:\Windows\System32\"
                                   Dim obj As New Object()
                                   If Directory.Exists(dir)Then
                                      Parallel.ForEach(Directory.GetFiles(dir), 
                                         Sub(f)
                                            If token.IsCancellationRequested Then
                                               token.ThrowIfCancellationRequested()
                                            End If  
                                            Dim fi As New FileInfo(f)
                                            SyncLock(obj)
                                              files.Add(Tuple.Create(fi.Name, fi.DirectoryName, fi.Length, fi.LastWriteTimeUtc))          
                                            End SyncLock
                                         End Sub)
                                   End If
                                End Sub, token)
      tokenSource.Cancel()
      Try
         t.Wait() 
         Console.WriteLine("Retrieved information for {0} files.", files.Count)
      Catch e As AggregateException
         Console.WriteLine("Exception messages:")
         For Each ie As Exception In e.InnerExceptions
            Console.WriteLine("   {0}:{1}", ie.GetType().Name, ie.Message)
         Next
         Console.WriteLine()
         Console.WriteLine("Task status: {0}", t.Status)       
      Finally
         tokenSource.Dispose()
      End Try
   End Sub
End Module
' The example displays the following output:
'       Exception messages:
'          TaskCanceledException: A task was canceled.
'       
'       Task status: Canceled

備註

呼叫 StartNew 在功能上等同於使用其中一個建構子建立任務，然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Task.Run(Action, CancellationToken) 方法快速呼叫 StartNew(Action, CancellationToken)，並使用預設參數。 不過請注意，兩種方法在行為上有差異： Task.Run(Action, CancellationToken) 預設情況下，不允許有選項的子任務 TaskCreationOptions.AttachedToParent 附加到目前 Task 實例，而 StartNew(Action, CancellationToken) 則允許。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
 System::Threading::Tasks::Task ^ StartNew(Action ^ action, System::Threading::Tasks::TaskCreationOptions creationOptions);

public System.Threading.Tasks.Task StartNew(Action action, System.Threading.Tasks.TaskCreationOptions creationOptions);

member this.StartNew : Action * System.Threading.Tasks.TaskCreationOptions -> System.Threading.Tasks.Task

Public Function StartNew (action As Action, creationOptions As TaskCreationOptions) As Task

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其中一個建構子建立任務，然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
 System::Threading::Tasks::Task ^ StartNew(Action ^ action);

public System.Threading.Tasks.Task StartNew(Action action);

member this.StartNew : Action -> System.Threading.Tasks.Task

Public Function StartNew (action As Action) As Task

參數

傳回

開始的任務。

例外狀況

範例

以下範例使用此 StartNew(Action) 方法，反覆呼叫 Action 一個代理，該代理產生隨機數，將其解讀為 Unicode 碼點，轉換為 UTF16 編碼的碼單元，並顯示產生的字元資訊。

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

public class Example
{
   public static void Main()
   {
      Random rnd = new Random();
      List<Task> tasks  = new List<Task>();
      // Execute the task 10 times.
      for (int ctr = 1; ctr <= 9; ctr++) {
         tasks.Add(Task.Factory.StartNew( () => {
                                            int utf32 = 0;
                                            lock(rnd) {
                                               // Get UTF32 value.
                                               utf32 = rnd.Next(0, 0xE01F0);
                                            }
                                            // Convert it to a UTF16-encoded character.
                                            string utf16 = Char.ConvertFromUtf32(utf32);
                                            // Display information about the character.
                                            Console.WriteLine("0x{0:X8} --> '{1,2}' ({2})", 
                                                              utf32, utf16, ShowHex(utf16));
                                         }));                           
      }
      Task.WaitAll(tasks.ToArray()); 
   }

   private static string ShowHex(string value)
   {
      string hexString = null;
      // Handle only non-control characters.
      if (!Char.IsControl(value, 0)) {
         foreach (var ch in value)
            hexString += $"0x{(ushort)ch:X} ";
      }   
      return hexString.Trim();
   }
}
// The example displays the following output:
//       0x00097103 --> '򗄃' (0x55836 0x56579)
//       0x000A98A1 --> '򩢡' (0x55910 0x56481)
//       0x00050002 --> '񐀂' (0x55552 0x56322)
//       0x0000FEF1 --> 'ﻱ' (0x65265)
//       0x0008BC0A --> '򋰊' (0x55791 0x56330)
//       0x000860EA --> '򆃪' (0x55768 0x56554)
//       0x0009AC5A --> '򚱚' (0x55851 0x56410)
//       0x00053320 --> '񓌠' (0x55564 0x57120)
//       0x000874EF --> '򇓯' (0x55773 0x56559)

Imports System.Collections.Generic
Imports System.Threading.Tasks

Public Module Example
   Public Sub Main()
      Dim rnd As New Random()
      Dim tasks As New List(Of Task)
      ' Execute the task 10 times.
      For ctr As Integer = 1 To 9
         tasks.Add(Task.Factory.StartNew(Sub()
                                            Dim utf32 As Integer
                                            SyncLock(rnd)
                                               ' Get UTF32 value.
                                               utf32 = rnd.Next(0, &hE01F0)
                                            End SyncLock
                                            ' Convert it to a UTF16-encoded character.
                                            Dim utf16 As String = Char.ConvertFromUtf32(utf32)
                                            ' Display information about the character.
                                            Console.WriteLine("0x{0:X8} --> '{1,2}' ({2})", 
                                                              utf32, utf16, ShowHex(utf16))
                                         End Sub))                           
      Next
      Task.WaitAll(tasks.ToArray()) 
   End Sub
   
   Private Function ShowHex(value As String) As String
      Dim hexString As String = Nothing
      ' Handle only non-control characters.
      If Not Char.IsControl(value, 0) Then
         For Each ch In value
            hexString += String.Format("0x{0} ", Convert.ToUInt16(ch))
         Next
      End If   
      Return hexString.Trim()
   End Function
End Module
' The example displays output similar to the following:
'       0x00097103 --> '򗄃' (0x55836 0x56579)
'       0x000A98A1 --> '򩢡' (0x55910 0x56481)
'       0x00050002 --> '񐀂' (0x55552 0x56322)
'       0x0000FEF1 --> 'ﻱ' (0x65265)
'       0x0008BC0A --> '򋰊' (0x55791 0x56330)
'       0x000860EA --> '򆃪' (0x55768 0x56554)
'       0x0009AC5A --> '򚱚' (0x55851 0x56410)
'       0x00053320 --> '񓌠' (0x55564 0x57120)
'       0x000874EF --> '򇓯' (0x55773 0x56559)

備註

呼叫 StartNew 在功能上等同於使用其中一個建構子建立任務，然後呼叫 Task.Start 該方法來排程執行該任務。

從 .NET Framework 4.5 開始，你可以使用 Task.Run(Action) 方法快速呼叫 StartNew(Action)，並使用預設參數。 不過請注意，兩種方法在行為上有差異： Task.Run(Action) 預設情況下，不允許有選項的子任務 TaskCreationOptions.AttachedToParent 附加到目前 Task 實例，而 StartNew(Action) 則允許。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
 System::Threading::Tasks::Task ^ StartNew(Action<System::Object ^> ^ action, System::Object ^ state);

public System.Threading.Tasks.Task StartNew(Action<object> action, object state);

public System.Threading.Tasks.Task StartNew(Action<object?> action, object? state);

member this.StartNew : Action<obj> * obj -> System.Threading.Tasks.Task

Public Function StartNew (action As Action(Of Object), state As Object) As Task

參數

傳回

開始的任務。

例外狀況

範例

以下範例定義了一個由六字母組成的詞彙陣列。 每個字會交給 Action<T> 一位代表，代表會將字詞打亂並顯示原始字及其打亂後的版本。

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

public class Example
{
   public static void Main()
   {
      var tasks = new List<Task>();
      Random rnd = new Random();
      Object lockObj = new Object();
      String[] words6 = { "reason", "editor", "rioter", "rental",
                          "senior", "regain", "ordain", "rained" };

      foreach (var word6 in words6)
         tasks.Add(Task.Factory.StartNew( (word) => { Char[] chars = word.ToString().ToCharArray();
                                                      double[] order = new double[chars.Length];
                                                      lock (lockObj) {
                                                         for (int ctr = 0; ctr < order.Length; ctr++)
                                                             order[ctr] = rnd.NextDouble();
                                                      }
                                                      Array.Sort(order, chars);
                                                      Console.WriteLine("{0} --> {1}", word,
                                                                        new String(chars));
                                                    }, word6));

      Task.WaitAll(tasks.ToArray());
   }
}
// The example displays output like the following:
//    regain --> irnaeg
//    ordain --> rioadn
//    reason --> soearn
//    rained --> rinade
//    rioter --> itrore
//    senior --> norise
//    rental --> atnerl
//    editor --> oteird

Imports System.Collections.Generic
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim tasks As New List(Of Task)()
      Dim rnd As New Random()
      Dim lockObj As New Object()
      Dim words6() As String = { "reason", "editor", "rioter", "rental",
                                 "senior", "regain", "ordain", "rained" }

      For Each word6 in words6
         tasks.Add(Task.Factory.StartNew( Sub(word)
                                              Dim chars() As Char = word.ToString().ToCharArray()
                                              Dim order(chars.Length - 1) As Double
                                              SyncLock lockObj
                                                 For ctr As Integer = 0 To order.Length - 1
                                                    order(ctr) = rnd.NextDouble()
                                                 Next
                                              End SyncLock
                                              Array.Sort(order, chars)
                                              Console.WriteLine("{0} --> {1}", word,
                                                                new String(chars))
                                          End Sub, word6))
      Next
      Task.WaitAll(tasks.ToArray())
   End Sub
End Module
' The example displays output like the following:
'       regain --> irnaeg
'       ordain --> rioadn
'       reason --> soearn
'       rained --> rinade
'       rioter --> itrore
'       senior --> norise
'       rental --> atnerl
'       editor --> oteird

請注意，範例初始化了一個隨機數產生器，該生成器受到鎖的保護。 關於鎖的需求，請參見課程主題中的 Random 「The System.Random class and thread safety」。

備註

呼叫 StartNew 在功能上等同於使用其建構子創建 a Task ，然後呼叫 Start 該方法來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ StartNew(Func<TResult> ^ function, System::Threading::CancellationToken cancellationToken, System::Threading::Tasks::TaskCreationOptions creationOptions, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<TResult> function, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskCreationOptions creationOptions, System.Threading.Tasks.TaskScheduler scheduler);

member this.StartNew : Func<'Result> * System.Threading.CancellationToken * System.Threading.Tasks.TaskCreationOptions * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task<'Result>

Public Function StartNew(Of TResult) (function As Func(Of TResult), cancellationToken As CancellationToken, creationOptions As TaskCreationOptions, scheduler As TaskScheduler) As Task(Of TResult)

類型參數

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其其中一個建構子建立 ， Task<TResult> 然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew 條目。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ StartNew(Func<TResult> ^ function);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<TResult> function);

member this.StartNew : Func<'Result> -> System.Threading.Tasks.Task<'Result>

Public Function StartNew(Of TResult) (function As Func(Of TResult)) As Task(Of TResult)

類型參數

參數

傳回

開始的任務。

例外狀況

範例

以下範例是一個簡單的加法應用程式，會產生兩個隨機數，並提示使用者輸入他們的總和。 接著它會指示答案是否正確，或若使用者的回答不是有效的號碼，則提示使用者重新輸入有效號碼。 用來 StartNew 建立 Task<TResult> 回傳隨機數以相加的物件。

using System;
using System.Threading.Tasks;

public class Example
{
   public static void Main()
   {
      Random rnd = new Random();
      Task<int>[] tasks = new Task<int>[2];
      Object obj = new Object();
      
      while (true) {
         for (int ctr = 0; ctr <= 1; ctr++)
            tasks[ctr] = Task.Factory.StartNew(() => { int i = 0;
                                                       lock(obj) {
                                                          i = rnd.Next(101);
                                                       }
                                                       return i; });

         Task.WaitAll(tasks);
         int n1 = tasks[0].Result;
         int n2 = tasks[1].Result;
         int result = n1 + n2;
         bool validInput = false;
         while (!validInput) {
            ShowMessage(n1, n2);
            string userInput = Console.ReadLine();
            // Process user input.
            if (userInput.Trim().ToUpper() == "X") return;
            int answer;
            validInput = Int32.TryParse(userInput, out answer);
            if (!validInput)
               Console.WriteLine("Invalid input. Try again, but enter only numbers. ");
            else if (answer == result)
               Console.WriteLine("Correct!");
            else
               Console.WriteLine("Incorrect. The correct answer is {0}.", result);
         }
      }
   }

   private static void ShowMessage(int n1, int n2)
   {
      Console.WriteLine("\nEnter 'x' to exit...");
      Console.Write("{0} + {1} = ", n1, n2);
   }
}
// The example displays the following output:
//       Enter 'x' to exit...
//       15 + 11 = 26
//       Correct!
//
//       Enter 'x' to exit...
//       75 + 33 = adc
//       Invalid input. Try again, but enter only numbers.
//
//       Enter 'x' to exit...
//       75 + 33 = 108
//       Correct!
//
//       Enter 'x' to exit...
//       67 + 55 = 133
//       Incorrect. The correct answer is 122.
//
//       Enter 'x' to exit...
//       92 + 51 = 133
//       Incorrect. The correct answer is 143.
//
//       Enter 'x' to exit...
//       81 + 65 = x

   
Imports System.Threading.Tasks

Module AdditionTester
   Public Sub Main()
      Dim rnd As New Random()
      Dim tasks(1) As Task(Of Integer)
      Dim obj As New Object()
      
      Do While True
         For ctr As Integer = 0 To 1
            tasks(ctr) = Task.Factory.StartNew(Function()
                                                  Dim i As Integer
                                                  SyncLock(obj)
                                                     i = rnd.Next(101)
                                                  End SyncLock
                                                  Return i
                                               End Function)
         Next
         Task.WaitAll(tasks)
         Dim n1 As Integer = tasks(0).Result
         Dim n2 As Integer = tasks(1).Result
         Dim result As Integer = n1 + n2
         Dim validInput As Boolean = False
         Do While Not validInput
            ShowMessage(n1, n2)
            Dim userInput As String = Console.ReadLine()
            ' Process user input.
            If userInput.Trim().ToUpper = "X" Then Exit Sub
            Dim answer As Integer
            validInput = Int32.TryParse(userInput, answer)
            If Not validInput Then
               Console.WriteLine("Invalid input. Try again, but enter only numbers. ")
            Else If answer = result Then
               Console.WriteLine("Correct!")
            Else
               Console.WriteLine("Incorrect. The correct answer is {0}.", result)
            End If
         Loop
      Loop
   End Sub
   
   Private Sub ShowMessage(n1 As Integer, n2 As Integer)
      Console.WriteLine()
      Console.WriteLine("Enter 'x' to exit...")
      Console.Write("{0} + {1} = ", n1, n2)
   End Sub
End Module
' The example displays output like the following:
'       Enter 'x' to exit...
'       15 + 11 = 26
'       Correct!
'
'       Enter 'x' to exit...
'       75 + 33 = adc
'       Invalid input. Try again, but enter only numbers.
'
'       Enter 'x' to exit...
'       75 + 33 = 108
'       Correct!
'
'       Enter 'x' to exit...
'       67 + 55 = 133
'       Incorrect. The correct answer is 122.
'
'       Enter 'x' to exit...
'       92 + 51 = 133
'       Incorrect. The correct answer is 143.
'
'       Enter 'x' to exit...
'       81 + 65 = x

備註

呼叫 StartNew 在功能上等同於使用其其中一個建構子建立 ， Task<TResult> 然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以呼叫 Task.Run<TResult>(Func<TResult>) 方法，快速呼叫 StartNew，並使用預設參數。 不過請注意，兩種方法在行為上有差異： Task.Run<TResult>(Func<TResult>) 預設情況下，不允許有選項的子任務 TaskCreationOptions.AttachedToParent 附加到目前 Task<TResult> 實例，而 StartNew<TResult>(Func<TResult>) 則允許。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew 條目。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ StartNew(Func<System::Object ^, TResult> ^ function, System::Object ^ state);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<object,TResult> function, object state);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<object?,TResult> function, object? state);

member this.StartNew : Func<obj, 'Result> * obj -> System.Threading.Tasks.Task<'Result>

Public Function StartNew(Of TResult) (function As Func(Of Object, TResult), state As Object) As Task(Of TResult)

類型參數

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其其中一個建構子建立 ， Task<TResult> 然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew 條目。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ StartNew(Func<TResult> ^ function, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<TResult> function, System.Threading.CancellationToken cancellationToken);

member this.StartNew : Func<'Result> * System.Threading.CancellationToken -> System.Threading.Tasks.Task<'Result>

Public Function StartNew(Of TResult) (function As Func(Of TResult), cancellationToken As CancellationToken) As Task(Of TResult)

類型參數

參數

傳回

開始的任務。

例外狀況

範例

以下範例使用兩個任務來計算以 F100 = F100-1 + F100-2 結尾的費波那契數列，種子值為 F1=1、F2 = 1 和 F1 = 0， F2=1。 大約一半的時間，在操作執行時會設定取消標記。 範例輸出顯示若兩項任務成功完成且代幣被取消，結果如何。

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

public class Example
{
   public static void Main()
   {
      var rnd = new Random();
      var tasks = new List<Task<BigInteger[]>>();
      var source = new CancellationTokenSource();
      var token = source.Token;
      for (int ctr = 0; ctr <= 1; ctr++) {
         int start = ctr;
         tasks.Add(Task.Run( () => { BigInteger[] sequence = new BigInteger[100];
                                     sequence[0] = start;
                                     sequence[1] = 1;
                                     for (int index = 2; index <= sequence.GetUpperBound(0); index++) {
                                        token.ThrowIfCancellationRequested();
                                        sequence[index] = sequence[index - 1] + sequence[index - 2];
                                     }
                                     return sequence;
                                   }, token));
      }
      if (rnd.Next(0, 2) == 1)
         source.Cancel();
      try {
         Task.WaitAll(tasks.ToArray());
         foreach (var t in tasks)
            Console.WriteLine("{0}, {1}...{2:N0}", t.Result[0], t.Result[1],
                              t.Result[99]);
      }
      catch (AggregateException e) {
         foreach (var ex in e.InnerExceptions)
            Console.WriteLine("{0}: {1}", ex.GetType().Name, ex.Message);
      }
   }
}
// The example displays either the following output:
//    0, 1...218,922,995,834,555,169,026
//    1, 1...354,224,848,179,261,915,075
// or the following output:
//    TaskCanceledException: A task was canceled.
//    TaskCanceledException: A task was canceled.

Imports System.Collections.Generic
Imports System.Numerics
Imports System.Threading
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim rnd As New Random()
      Dim tasks As New List(Of Task(Of BigInteger()))
      Dim source As New CancellationTokenSource
      Dim token As CancellationToken = source.Token
      For ctr As Integer = 0 To 1
         Dim start As Integer = ctr
         tasks.Add(Task.Run(Function()
                               Dim sequence(99) As BigInteger
                               sequence(0) = start
                               sequence(1) = 1
                               For index As Integer = 2 To sequence.GetUpperBound(0)
                                  token.ThrowIfCancellationRequested()
                                  sequence(index) = sequence(index - 1) + sequence(index - 2)
                               Next
                               Return sequence
                            End Function, token))
      Next
      If rnd.Next(0, 2) = 1 Then source.Cancel
      Try
         Task.WaitAll(tasks.ToArray())
         For Each t In tasks
            Console.WriteLine("{0}, {1}...{2:N0}", t.Result(0), t.Result(1),
                              t.Result(99))
         Next
      Catch e As AggregateException
         For Each ex In e.InnerExceptions
            Console.WriteLine("{0}: {1}", ex.GetType().Name, ex.Message)
         Next
      End Try
   End Sub
End Module
' The example displays either the following output:
'    0, 1...218,922,995,834,555,169,026
'    1, 1...354,224,848,179,261,915,075
' or the following output:
'    TaskCanceledException: A task was canceled.
'    TaskCanceledException: A task was canceled.

備註

呼叫 StartNew 在功能上等同於使用其其中一個建構子建立 ， Task<TResult> 然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Task.Run<TResult>(Func<TResult>, CancellationToken) 方法快速呼叫 StartNew<TResult>(Func<TResult>, CancellationToken)，並使用預設參數。 不過請注意，兩種方法在行為上有差異： Task.Run<TResult>(Func<TResult>, CancellationToken) 預設情況下，不允許有選項的子任務 TaskCreationOptions.AttachedToParent 附加到目前 Task<TResult> 實例，而 StartNew<TResult>(Func<TResult>, CancellationToken) 則允許。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew 條目。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ StartNew(Func<TResult> ^ function, System::Threading::Tasks::TaskCreationOptions creationOptions);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<TResult> function, System.Threading.Tasks.TaskCreationOptions creationOptions);

member this.StartNew : Func<'Result> * System.Threading.Tasks.TaskCreationOptions -> System.Threading.Tasks.Task<'Result>

Public Function StartNew(Of TResult) (function As Func(Of TResult), creationOptions As TaskCreationOptions) As Task(Of TResult)

類型參數

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其其中一個建構子建立 ， Task<TResult> 然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew 條目。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ StartNew(Func<System::Object ^, TResult> ^ function, System::Object ^ state, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<object,TResult> function, object state, System.Threading.CancellationToken cancellationToken);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<object?,TResult> function, object? state, System.Threading.CancellationToken cancellationToken);

member this.StartNew : Func<obj, 'Result> * obj * System.Threading.CancellationToken -> System.Threading.Tasks.Task<'Result>

Public Function StartNew(Of TResult) (function As Func(Of Object, TResult), state As Object, cancellationToken As CancellationToken) As Task(Of TResult)

類型參數

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其其中一個建構子建立 ， Task<TResult> 然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew 條目。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ StartNew(Func<System::Object ^, TResult> ^ function, System::Object ^ state, System::Threading::Tasks::TaskCreationOptions creationOptions);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<object,TResult> function, object state, System.Threading.Tasks.TaskCreationOptions creationOptions);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<object?,TResult> function, object? state, System.Threading.Tasks.TaskCreationOptions creationOptions);

member this.StartNew : Func<obj, 'Result> * obj * System.Threading.Tasks.TaskCreationOptions -> System.Threading.Tasks.Task<'Result>

Public Function StartNew(Of TResult) (function As Func(Of Object, TResult), state As Object, creationOptions As TaskCreationOptions) As Task(Of TResult)

類型參數

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其其中一個建構子建立 ， Task<TResult> 然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew 條目。

另請參閱

• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

來源:

TaskFactory.cs

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ StartNew(Func<System::Object ^, TResult> ^ function, System::Object ^ state, System::Threading::CancellationToken cancellationToken, System::Threading::Tasks::TaskCreationOptions creationOptions, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<object,TResult> function, object state, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskCreationOptions creationOptions, System.Threading.Tasks.TaskScheduler scheduler);

public System.Threading.Tasks.Task<TResult> StartNew<TResult>(Func<object?,TResult> function, object? state, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskCreationOptions creationOptions, System.Threading.Tasks.TaskScheduler scheduler);

member this.StartNew : Func<obj, 'Result> * obj * System.Threading.CancellationToken * System.Threading.Tasks.TaskCreationOptions * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task<'Result>

Public Function StartNew(Of TResult) (function As Func(Of Object, TResult), state As Object, cancellationToken As CancellationToken, creationOptions As TaskCreationOptions, scheduler As TaskScheduler) As Task(Of TResult)

類型參數

參數

傳回

開始的任務。

例外狀況

備註

呼叫 StartNew 在功能上等同於使用其其中一個建構子建立 ， Task<TResult> 然後呼叫 Start 來排程執行。

從 .NET Framework 4.5 開始，你可以使用 Run 方法搭配 Action 物件，快速呼叫 StartNew 並使用預設參數。 欲了解更多資訊與程式碼範例，請參閱 Parallel Programming with .NET 部落格中的 Task.Run 與 Task.Factory.StartNew 條目。

另請參閱

• TaskScheduler
• 工作平行程式庫 (TPL)
• 使用接續工作串聯任務
• 工作取消