WF工作流与Web服务的相互调用 —— WF与WCF互相调用（利用ReceiveActivity把WF发布为WCF)...

前几篇文章已经为大家介绍过Web服务与Workflow工作流之间的相互调用的方法，在这两篇文章里面开始为大家介绍一下WCF与 Workflow工作流之间的关系。微软在WCF和WF之间扩展了强大的功能，使用两者能够协调工作，在.NET Framework3.5中既可以把Workflow发布为WCF实现工作流服务，也可以在WCF中调用Workflow工作流，增强其使用的灵活性。

下面先为大家介绍如何把Workflow工作流发布为WCF服务,这里还是以最简单的Hello World为例子。

首先设定一个服务契约接口

View Code

namespace Microsoft.IService
{
[ServiceContract(SessionMode = SessionMode.NotAllowed)] // 这里先使用最简单的无状态服务为例子
public interface IWorkflowService
{
[OperationContract]
string Hello( string name);
}
}

现在新建一个Workflow，加入ReceiveActivity活动receiveActivity1，ReceiveActivity实现了 IEventActivity，可以作为EventDrivenActivity的第一个子活动,然后在receiveActivity1中加入 codeActivity1来执行操作。

现在先把receiveActivity1属性ServiceOperationInfo绑 定为刚设定的服务接口Microsoft.ISercive.IWorkflowService,在后台添加两个变量_returnValue和name 分别用来绑定返回值和输入参数。

 

然后把receiveActivity1的属性CanCreateInstance设置为True，这代表着每次被客户端调用的时候都创建一个新的对象实例。

 

现在应该为codeActivity1添加ExecuteCode事件的方法codeActivity1_ExecuteCode，下面为这个Workflow的完整代码。

View Code

namespace Microsoft.Workflow
{
public sealed partial class Workflow4 : SequentialWorkflowActivity
{
public string _name;
public string returnValue;

public Workflow4()
{
InitializeComponent();
}

private void codeActivity1_ExecuteCode( object sender, EventArgs e)
{
returnValue = " Hello " + _name;
}
}
}

现在可以为这个服务建立一个*.svc文件了，注意Service用于绑定此Workflow类文件的全名称

<%@ ServiceHost Language="C#" Debug="true" Service="Microsoft.Workflow.Workflow4 " Factory="System.ServiceModel.Activation.WorkflowServiceHostFactory" %>

然后实现*.config配置

 

View Code

< configuration >

< system.serviceModel >
< behaviors >
< serviceBehaviors >
< behavior name = " ServiceBehavior " >
< serviceMetadata httpGetEnabled = " true " />
< serviceDebug includeExceptionDetailInFaults = " false " />
behavior >
serviceBehaviors >
behaviors >
< services >
< service behaviorConfiguration = " ServiceBehavior " name = " Microsoft.Workflow.Workflow4 " >
< endpoint address = "" binding = " wsHttpBinding " contract = " Microsoft.IService.IWorkflowService " > // 注意service Name是此Workflow工作流的全名称，而contract是该服务契约的全名称
< identity >
< dns value = " localhost " />
identity >
endpoint >
< endpoint address = " mex " binding = " mexHttpBinding " contract = " IMetadataExchange " />
service >
services >
system.serviceModel >
configuration >

现在服务器端的开发已经完成，可以开发一个客户端进行测试。我们在客户端引用此Web服务，然后配置好.config文件。

 

View Code

< configuration >
< system.serviceModel >
< bindings >
< wsHttpBinding >
// 添加服务绑定配置，设置其接收时间，事务，最大接收量等等属性
< binding name = " WSHttpBinding_IWorkflowService " closeTimeout = " 00:01:00 "
openTimeout = " 00:01:00 " receiveTimeout = " 00:10:00 " sendTimeout = " 00:01:00 "
bypassProxyOnLocal = " false " transactionFlow = " false " hostNameComparisonMode = " StrongWildcard "
maxBufferPoolSize = " 524288 " maxReceivedMessageSize = " 65536 " messageEncoding = " Text "
textEncoding = " utf-8 " useDefaultWebProxy = " true " allowCookies = " false " >
< readerQuotas maxDepth = " 32 " maxStringContentLength = " 8192 " maxArrayLength = " 16384 "
maxBytesPerRead = " 4096 " maxNameTableCharCount = " 16384 " />
< reliableSession ordered = " true " inactivityTimeout = " 00:10:00 "
enabled = " false " />
< security mode = " Message " >
< transport clientCredentialType = " Windows " proxyCredentialType = " None "
realm = "" />
< message clientCredentialType = " Windows " negotiateServiceCredential = " true "
algorithmSuite = " Default " />
security >
binding >
wsHttpBinding >
bindings >
< client >
// 绑定其地址，服务契约等等属性
< endpoint address = " http://leslie-pc:5600/Service.svc " binding = " wsHttpBinding "
bindingConfiguration = " WSHttpBinding_IWorkflowService " contract = " ServiceReference1.IWorkflowService "
name = " WSHttpBinding_IWorkflowService " >
< identity >
< dns value = " localhost " />
identity >
endpoint >
client >
system.serviceModel >
configuration >

测试

 

View Code

static void Main( string [] args)
{
try
{
WorkflowService.WorkflowServiceClient workflowService1 = new WorkflowService.WorkflowServiceClient();
workflowService1.Hello( " Leslie " );
}
catch (Exception ex)
{...}
Console.ReadKey();
}

结果显示：

Hello Leslie

 

经过简单的测试，证明此工作流服务已经能正常运行。使用此方式，可以轻松地Workflow发布为WCF服务而不需要编写任何干预探测代码，但值得注意的是WCF支持请求/响应，单向，双向多个工作模式，但Workflow工作流则只支持请求/响应这种模式。

微软一开始就注意把WCF与WF结合开发实现简单的相互调用，在下一篇文章将为你介绍一下如何使用SendActivity在Workflow工作流里面直接调用WCF服务。

 

WF工作流与Web服务的相互调用 —— 通过Web服务调用Workflow工作流（基础实例）
WF工作流与Web服务的相互调用 —— 通过Web服务调用Workflow工作流（开发持久化工作流）
WF工作流与Web服务的相互调用 —— 以InvokeWebServiceActivity在Workflow工作流调用Web服务
WF工作流与Web服务的相互调用 —— WF与WCF互相调用（利用ReceiveActivity把WF发布为WCF)