本文整理汇总了VB.NET中System.Threading.ThreadPool.QueueUserWorkItem方法的典型用法代码示例。如果您正苦于以下问题：VB.NET ThreadPool.QueueUserWorkItem方法的具体用法？VB.NET ThreadPool.QueueUserWorkItem怎么用？VB.NET ThreadPool.QueueUserWorkItem使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类System.Threading.ThreadPool的用法示例。
在下文中一共展示了ThreadPool.QueueUserWorkItem方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的VB.NET代码示例。
示例1: Example
' 导入命名空间
Imports System.Threading
Public Module Example
Public Sub Main()
' Queue the work for execution.
ThreadPool.QueueUserWorkItem(AddressOf ThreadProc)
Console.WriteLine("Main thread does some work, then sleeps.")
Thread.Sleep(1000)
Console.WriteLine("Main thread exits.")
End Sub
' This thread procedure performs the task.
Sub ThreadProc(stateInfo As Object)
' No state object was passed to QueueUserWorkItem, so stateInfo is null.
Console.WriteLine("Hello from the thread pool.")
End Sub
End Module输出：
Main thread does some work, then sleeps. Hello from the thread pool. Main thread exits.
示例2: Fibonacci
' 导入命名空间
Imports System.Threading
Public Class Fibonacci
Private _doneEvent As ManualResetEvent
Public Sub New(n As Integer, doneEvent As ManualResetEvent)
Me.N = n
_doneEvent = doneEvent
End Sub
Public ReadOnly Property N As Integer
Public Property FibOfN As Integer
Public Sub ThreadPoolCallback(threadContext As Object)
Dim threadIndex As Integer = CType(threadContext, Integer)
Console.WriteLine($"Thread {threadIndex} started...")
FibOfN = Calculate(N)
Console.WriteLine($"Thread {threadIndex} result calculated...")
_doneEvent.Set()
End Sub
Public Function Calculate(n As Integer) As Integer
If (n <= 1) Then
Return n
End If
Return Calculate(n - 1) + Calculate(n - 2)
End Function
End Class
Public Class ThreadPoolExample
<MTAThread>
Public Shared Sub Main()
Const FibonacciCalculations As Integer = 5
Dim doneEvents(FibonacciCalculations - 1) As ManualResetEvent
Dim fibArray(FibonacciCalculations - 1) As Fibonacci
Dim rand As Random = New Random()
Console.WriteLine($"Launching {FibonacciCalculations} tasks...")
For i As Integer = 0 To FibonacciCalculations - 1
doneEvents(i) = New ManualResetEvent(False)
Dim f As Fibonacci = New Fibonacci(rand.Next(20, 40), doneEvents(i))
fibArray(i) = f
ThreadPool.QueueUserWorkItem(AddressOf f.ThreadPoolCallback, i)
Next
WaitHandle.WaitAll(doneEvents)
Console.WriteLine("All calculations are complete.")
For i As Integer = 0 To FibonacciCalculations - 1
Dim f As Fibonacci = fibArray(i)
Console.WriteLine($"Fibonacci({f.N}) = {f.FibOfN}")
Next
End Sub
End Class
' Output is similar to
' Launching 5 tasks...
' Thread 1 started...
' Thread 2 started...
' Thread 3 started...
' Thread 4 started...
' Thread 0 started...
' Thread 4 result calculated...
' Thread 2 result calculated...
' Thread 3 result calculated...
' Thread 0 result calculated...
' Thread 1 result calculated...
' All calculations are complete.
' Fibonacci(37) = 24157817
' Fibonacci(38) = 39088169
' Fibonacci(29) = 514229
' Fibonacci(32) = 2178309
' Fibonacci(23) = 28657