.net visual studio生成的Web服务客户端是否线程安全?
我们在一个项目中创建了一个服务引用 现在,我们在应用程序启动时创建一个实例。 同样,当应用程序统计时,我们为.net visual studio生成的Web服务客户端是否线程安全?,.net,vb.net,multithreading,web-services,wcf,.net,Vb.net,Multithreading,Web Services,Wcf,我们在一个项目中创建了一个服务引用 现在,我们在应用程序启动时创建一个实例。 同样,当应用程序统计时,我们为Service.Method1Completed,Service.Method2Completed等添加一个事件处理程序 然后在特定事件上,我们调用Service.Method1Async,Service.Method2Asyncect。注意,这些调用是由不同的线程发出的 但在某些计算机上,事件处理程序从未触发,因此我们开始检查FirstChanceExceptions,因为当发生这种情况
Service.Method1Completed
,Service.Method2Completed
等添加一个事件处理程序
然后在特定事件上,我们调用Service.Method1Async
,Service.Method2Async
ect。注意,这些调用是由不同的线程发出的
但在某些计算机上,事件处理程序从未触发,因此我们开始检查FirstChanceExceptions
,因为当发生这种情况时,会出现以下FirstChanceExceptions
System.Net.Sockets.SocketException提供的参数无效。vid System.Net.Sockets.Socket.SETSOCKET选项(SocketOptionLevel optionLevel,SocketOptionName optionName,Int32 optionValue,布尔值 (无声) System.ObjectDisposedException无法访问已处置的对象。 Objectname:System.Net.Sockets.NetworkStream。视频 System.Net.Sockets.NetworkStream.UnsafeBeginWrite(字节[]缓冲区,Int32 偏移量、Int32大小、异步回调、对象状态) System.Net.WebException请求已取消。
vid System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult) 这是使用服务引用的无效方式吗? 如果是这样的话,我如何在使用异步方法处理事件的同时正确地使用同步调用(请注意,im在.net 4.0和VS 2010上运行,因此
wait
是不可能的
服务器代码:
<ServiceContract()>
Public Interface IService1
<OperationContract()>
Function GetData(ByVal value As Integer) As String
End Interface
<ServiceBehavior(ConcurrencyMode:=ConcurrencyMode.Multiple, InstanceContextMode:=InstanceContextMode.Single, UseSynchronizationContext:=False)>
Public Class Service1
Implements IService1
Public Sub New()
End Sub
Public Function GetData(ByVal value As Integer) As String Implements IService1.GetData
Return String.Format("You entered: {0}", value)
End Function
End Class
它们不是线程安全的(例如,
ClientBase
不是)。但它们的制造和破坏成本很低。每个线程创建一个,甚至每个调用创建一个。无需同步。ClientBase可能不是线程安全的*因此派生代理也不是线程安全的,因此您不能以这种方式使用它们
您可以创建线程安全的基类,并自定义生成代理类
state
参数可用于将响应与传出请求相匹配。您将在回调事件的IAsyncResult.AsyncState中找到它
需要担心的一件事是,当多个请求通过同一个通道发送时,由于某些/任何原因,通道出现故障
*再看看这个问题:我创建了一个新项目,在这个项目中,我对一个Web服务进行了大量调用,每个请求有一个客户端,很抱歉,我仍然得到
ObjectDisposedException
(它们只是第一次出现的异常,我从未得到完整的回调…)好的,代码看起来不错。线程是一个风险区域,但除了count变量之外,我看不到任何共享状态。出于测试目的,将代码设为单线程。这个特定的问题还会发生吗?我只是尝试将代码更改为在MultipleClientInstances中只启动一个线程,然后我将调用数从400增加到4000,但仍然会出现错误……这不是线程问题。通过HTTP调用服务,并使用Fiddler查看HTTP和网络级别的错误。你发现了什么错误?如果有,发布有意义的截图。当我针对IIS运行客户端时,此错误停止发生,但我仍然发现服务器上的某些错误可能导致客户端内存泄漏,这令人不安。。。
<system.serviceModel>
<behaviors>
<serviceBehaviors>
<behavior>
<!-- To avoid disclosing metadata information, set the value below to false and remove the metadata endpoint above before deployment -->
<serviceMetadata httpGetEnabled="true"/>
<!-- To receive exception details in faults for debugging purposes, set the value below to true. Set to false before deployment to avoid disclosing exception information -->
<serviceDebug includeExceptionDetailInFaults="false"/>
<serviceThrottling maxConcurrentCalls="1000" maxConcurrentSessions="1000" maxConcurrentInstances="1000" />
</behavior>
</serviceBehaviors>
</behaviors>
<bindings>
<customBinding>
<binding>
<binaryMessageEncoding>
<readerQuotas maxArrayLength="5242880" />
</binaryMessageEncoding>
<httpTransport maxBufferPoolSize="52428800" maxReceivedMessageSize="5242880" maxBufferSize="5242880" authenticationScheme="Anonymous" />
</binding>
</customBinding>
</bindings>
<serviceHostingEnvironment multipleSiteBindingsEnabled="true" />
</system.serviceModel>
Imports System.Threading
Imports System.IO
Module Module1
Dim errorQueue As New System.Collections.Concurrent.ConcurrentBag(Of String)
Dim count As Integer
Sub Main()
AddHandler AppDomain.CurrentDomain.UnhandledException, AddressOf CurrentDomain_UnhandledException
AddHandler AppDomain.CurrentDomain.FirstChanceException, AddressOf AppDomain_FirstChanceException
MultipleClientInstances()
Console.WriteLine("Calls are in progress, press any key when they are done!")
Console.ReadKey()
Thread.MemoryBarrier()
errorQueue.Add("Number of requests remaining " + count.ToString())
Dim line As String = ""
Using writer As New StreamWriter("output.log")
While (errorQueue.TryTake(line))
writer.WriteLine(line)
End While
End Using
End Sub
Private Function GetClient() As ServiceReference1.Service1Client
Dim client As New ServiceReference1.Service1Client()
AddHandler client.GetDataCompleted, AddressOf client_GetDataCompleted
client.Open()
Return client
End Function
Private Sub MultipleClientInstances()
Console.WriteLine("Making calls!")
For i As Integer = 0 To 10
Dim t As New Thread(AddressOf MakeCallsWithNewClients)
t.Start()
Next
End Sub
Private Sub MakeCallsWithNewClients()
For i As Integer = 0 To 400
Interlocked.Increment(count)
Dim client As ServiceReference1.Service1Client = GetClient()
client.GetDataAsync(i, True)
While (Thread.VolatileRead(count) > 20)
Thread.Sleep(5)
End While
Next
End Sub
Private Sub client_GetDataCompleted(sender As Object, e As ServiceReference1.GetDataCompletedEventArgs)
Dim value As Integer = Interlocked.Decrement(count)
Console.WriteLine(value)
Dim client As ServiceReference1.Service1Client = CType(sender, ServiceReference1.Service1Client)
RemoveHandler client.GetDataCompleted, AddressOf client_GetDataCompleted
client.Close()
End Sub
Private Sub CurrentDomain_UnhandledException(ByVal sender As Object, ByVal e As UnhandledExceptionEventArgs)
If (e.ExceptionObject IsNot Nothing AndAlso e.ExceptionObject.GetType().IsSubclassOf(GetType(Exception))) Then
If (e.IsTerminating) Then
Console.WriteLine("Fatal exception occurred termination application, " + CType(e.ExceptionObject, Exception).ToString())
Else
Console.WriteLine("Unhandled exception occurred, " + CType(e.ExceptionObject, Exception).ToString())
End If
Else
If (e.IsTerminating) Then
Console.WriteLine("Fatal exception occurred termination application, " & e.ExceptionObject.ToString())
Else
Console.WriteLine("Unhandled exception occurred, " & e.ExceptionObject.ToString())
End If
End If
errorQueue.Add("UnhandledException: " + e.ExceptionObject.ToString())
End Sub
Private Sub AppDomain_FirstChanceException(ByVal sender As Object, ByVal e As Runtime.ExceptionServices.FirstChanceExceptionEventArgs)
Console.WriteLine("FirstChanceException: " + e.Exception.ToString())
errorQueue.Add("FirstChanceException: " + e.Exception.ToString())
End Sub
End Module