Question

当运行某些WCF服务的主机进程正在运行时 - 一切正常。但是当托管进程没有运行时--WCF无法创建对象并使用它。

换句话说 - 我有一个名为“ScrnSrvcR2.exe”的进程，它正在托管通过WCF公开的“ScreensApi”对象。因此，当“ScrnSrvcR2.exe”进程正在运行时，WCF客户端可以连接并使用“ScreensApi”对象。但是当“ScrnSrvcR2.exe”进程未运行时 - 客户端无法连接。

问题 - 是否可以通过第一个创建“ScreensApi”对象的请求自动启动远程系统（包括 localhost 作为远程系统的特定情况）？< / p>

因此，在这种情况下，当远程系统可以调用 CreateRemoteComObject 函数并且将启动对象托管过程时，我希望从WCF获得某种 DCOM样式功能自动并提供对象的实例。

是否可以使用WCF执行此操作？怎么样？

以下是一个我用来创建WCF对象的代码：

// this code works fine when "ScrnSrvcR2.exe" is running
protected void InitializeScreens()
{
    string endPointAddr = null;
    string transport = "net.tcp://";
    string hostAddress = "localhost";
    string servicePath = "ScreensApi";

    // [... optional reading of transport, hostAddress, servicePath values skipped... ]

    if (string.IsNullOrEmpty(endPointAddr))
        endPointAddr = transport + hostAddress + "/" + servicePath;

    System.ServiceModel.Channels.Binding bnd = null;
    NetTcpBinding tcpBinding = new NetTcpBinding();
    bnd = tcpBinding;
    tcpBinding.Name = "epNetTcp"; // this name is defined in config file

    EndpointAddress endpointAddress = new EndpointAddress(endPointAddr);

    bool isGoodProxy = false;
    try
    {
        try
        {
            this.ScreensProxy = new ScreensApiClient(bnd, endpointAddress);

            string un = null, pw = null;
            // [... optional reading of login/password skipped...]
            if (!string.IsNullOrEmpty(un) && !string.IsNullOrEmpty(pw))
            {
                ToLogger(TraceLevel.Verbose, string.Format("Station[ {0} ].Screens => Use credentials: {1}, {2}", this.Name, un, pw));
                this.ScreensProxy.ClientCredentials.UserName.UserName = un;
                this.ScreensProxy.ClientCredentials.UserName.Password = pw;
            }

            un = null; pw = null;
            // [... optional reading of login/password skipped...]
            if (!string.IsNullOrEmpty(un) && !string.IsNullOrEmpty(pw))
            {
                ToLogger(TraceLevel.Verbose, string.Format("Station[ {0} ].Screens => Use Windows-credentials: {1}, {2}", this.Name, un, pw));
                this.ScreensProxy.ClientCredentials.Windows.ClientCredential.UserName = un;
                this.ScreensProxy.ClientCredentials.Windows.ClientCredential.Password = pw;
            }

            this.ScreensProxy.Open();
            this.ScreensProxy.Ping(); // note: Ping() is a method of ScreensApi object, just to check if it is alive
            this.ScreensStationDescriptor = this.ScreensProxy.CreateStationDescriptor(this.Owner.Name, this.Name, CommonUtils.HostInfoStamp());
            this.ScreensProxy.InitializeStation(this.ScreensStationDescriptor);
            this.ScreensRuntimeContext = this.ScreensProxy.GetStationContext(this.ScreensStationDescriptor);

            isGoodProxy = true;
        }
        catch (Exception exc)
        {
            ToLogger(TraceLevel.Error, string.Format("Station[ {0} ].Screens -> {1}\n at {2}", this.Name, ErrorUtils.FormatErrorMsg(exc), exc.StackTrace));
            throw;
        }
    }
    finally
    {
        if (!isGoodProxy)
        {
            this.ScreensProxy = null;
            this.ScreensStationDescriptor = null;
            this.ScreensRuntimeContext = null;
            ToLogger(TraceLevel.Warning, string.Format("Station[ {0} ].Screens -> Remove ScreensProxy object ref as invalid!", this.Name));
        }
    }
}

我可能需要添加到我的代码中以使其自动启动WCF对象托管过程？

提前谢谢。

WCF - 可以远程创建对象吗？怎么样？

0 个答案: