通过

Thread.Priority 属性

  • 项目

获取或设置一个值，该值指示线程的调度优先级。

**命名空间:**System.Threading
**程序集:**mscorlib（在 mscorlib.dll 中）

语法

声明
Public Property Priority As ThreadPriority
用法
Dim instance As Thread
Dim value As ThreadPriority

value = instance.Priority

instance.Priority = value

public ThreadPriority Priority { get; set; }

public:
property ThreadPriority Priority {
    ThreadPriority get ();
    void set (ThreadPriority value);
}

/** @property */
public ThreadPriority get_Priority ()

/** @property */
public void set_Priority (ThreadPriority value)

public function get Priority () : ThreadPriority

public function set Priority (value : ThreadPriority)

属性值

ThreadPriority 值之一。默认值为 Normal。

异常

异常类型 条件

ThreadStateException

线程已到达最终状态，例如 Aborted。

ArgumentException

为设置操作指定的值不是有效的 ThreadPriority 值。

备注

可以为线程分配以下任何一个优先级值：

  • Highest

  • AboveNormal

  • Normal

  • BelowNormal

  • Lowest

不要求操作系统接受该线程优先级。

示例

下面的代码示例说明了更改线程优先级的结果。创建两个线程，其中一个线程的优先级设置为 BelowNormal。两个线程在 while 循环中都增加一个变量，并运行一段设定的时间。

Option Explicit
Option Strict

Imports System
Imports System.Threading

Public Class Test

    <MTAThread> _
    Shared Sub Main()
        Dim priorityTest As New PriorityTest()

        Dim threadOne As Thread = _
            New Thread(AddressOf priorityTest.ThreadMethod)
        threadOne.Name = "ThreadOne"
        Dim threadTwo As Thread = _
            New Thread(AddressOf priorityTest.ThreadMethod)
        threadTwo.Name = "ThreadTwo"

        threadTwo.Priority = ThreadPriority.BelowNormal
        threadOne.Start()
        threadTwo.Start()

        ' Allow counting for 10 seconds.
        Thread.Sleep(10000)
        priorityTest.LoopSwitch = False
    End Sub

End Class

Public Class PriorityTest

    Dim loopSwitchValue As Boolean 

    Sub New()
        loopSwitchValue = True
    End Sub

    WriteOnly Property LoopSwitch As Boolean
        Set
            loopSwitchValue = Value
        End Set
    End Property

    Sub ThreadMethod()
        Dim threadCount As Long = 0

        While loopSwitchValue
            threadCount += 1
        End While
        
        Console.WriteLine("{0} with {1,11} priority " & _
            "has a count = {2,13}", Thread.CurrentThread.Name, _
            Thread.CurrentThread.Priority.ToString(), _
            threadCount.ToString("N0")) 
    End Sub

End Class

using System;
using System.Threading;

class Test
{
    static void Main()
    {
        PriorityTest priorityTest = new PriorityTest();
        ThreadStart startDelegate = 
            new ThreadStart(priorityTest.ThreadMethod);

        Thread threadOne = new Thread(startDelegate);
        threadOne.Name = "ThreadOne";
        Thread threadTwo = new Thread(startDelegate);
        threadTwo.Name = "ThreadTwo";

        threadTwo.Priority = ThreadPriority.BelowNormal;
        threadOne.Start();
        threadTwo.Start();

        // Allow counting for 10 seconds.
        Thread.Sleep(10000);
        priorityTest.LoopSwitch = false;
    }
}

class PriorityTest
{
    bool loopSwitch;

    public PriorityTest()
    {
        loopSwitch = true;
    }

    public bool LoopSwitch
    {
        set{ loopSwitch = value; }
    }

    public void ThreadMethod()
    {
        long threadCount = 0;

        while(loopSwitch)
        {
            threadCount++;
        }
        Console.WriteLine("{0} with {1,11} priority " +
            "has a count = {2,13}", Thread.CurrentThread.Name, 
            Thread.CurrentThread.Priority.ToString(), 
            threadCount.ToString("N0")); 
    }
}

using namespace System;
using namespace System::Threading;
ref class PriorityTest
{
private:
   bool loopSwitch;

public:
   PriorityTest()
   {
      loopSwitch = true;
   }


   property bool LoopSwitch 
   {
      void set( bool value )
      {
         loopSwitch = value;
      }

   }
   void ThreadMethod()
   {
      __int64 threadCount = 0;
      while ( loopSwitch )
      {
         threadCount++;
      }

      Console::WriteLine( "{0} with {1,11} priority "
      "has a count = {2,13}", Thread::CurrentThread->Name, Thread::CurrentThread->Priority.ToString(), threadCount.ToString(  "N0" ) );
   }

};

int main()
{
   PriorityTest^ priorityTest = gcnew PriorityTest;
   ThreadStart^ startDelegate = gcnew ThreadStart( priorityTest, &PriorityTest::ThreadMethod );
   Thread^ threadOne = gcnew Thread( startDelegate );
   threadOne->Name =  "ThreadOne";
   Thread^ threadTwo = gcnew Thread( startDelegate );
   threadTwo->Name =  "ThreadTwo";
   threadTwo->Priority = ThreadPriority::BelowNormal;
   threadOne->Start();
   threadTwo->Start();
   
   // Allow counting for 10 seconds.
   Thread::Sleep( 10000 );
   priorityTest->LoopSwitch = false;
}

import System.*;
import System.Threading.*;
import System.Threading.Thread;

class Test
{
    public static void main(String[] args)
    {
        PriorityTest priorityTest = new PriorityTest();
        ThreadStart startDelegate = new ThreadStart(priorityTest.ThreadMethod);
        Thread threadOne = new Thread(startDelegate);

        threadOne.set_Name("ThreadOne");

        Thread threadTwo = new Thread(startDelegate);

        threadTwo.set_Name("ThreadTwo");
        threadTwo.set_Priority(ThreadPriority.BelowNormal);
        threadOne.Start();
        threadTwo.Start();

        // Allow counting for 10 seconds.
        Thread.Sleep(10000);
        priorityTest.set_LoopSwitch(false);
    } //main
} //Test

class PriorityTest
{
    private boolean loopSwitch;

    public PriorityTest()
    {
        loopSwitch = true;
    } //PriorityTest

    /** @property 
     */
    public void set_LoopSwitch(boolean value)
    {
        loopSwitch = value;
    } //set_LoopSwitch

    public void ThreadMethod()
    {
        long threadCount = 0;

        while (loopSwitch) {
            threadCount++;
        }

        Console.WriteLine("{0} with {1,11} priority " + "has a count = {2,13}",
            Thread.get_CurrentThread().get_Name(),
            Thread.get_CurrentThread().get_Priority().toString(),
            ((System.Int32)threadCount).ToString("N0"));
    } //ThreadMethod
} //PriorityTest

平台

Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。

版本信息

.NET Framework

受以下版本支持：2.0、1.1、1.0

.NET Compact Framework

受以下版本支持：2.0、1.0

请参见

参考

Thread 类
Thread 成员
System.Threading 命名空间
ThreadPriority

其他资源

调度线程