After you have created the service interface, you can then add the ReceiveActivity activity to the workflow and configure it to respond to method invocations on the service process.
WF enables workflows to interact with WCF and call methods that are exposed by a service. WF also enables you to host workflows in a service, which exposes workflow functionality to applications that run across a network or on the Internet and enables cross-platform invocation of workflow code.
When you add a SendActivity activity to your workflow, it contains the standard properties that are required to implement the SendActivity functionality.
Before you can invoke methods on the service, you must add a service reference to your project. To do this, right-click the workflow project node, and then click Add Service Reference. Use the Add Service Reference dialog box to retrieve the service information and add the reference to the project.
WCF is a programming model for building service-oriented applications. It enables developers to build reliable, secure, transaction-enabled solutions across platforms. WCF also provides the ability to implement legacy systems. By using WCF and WF, you can exploit the advantages of WCF security and stability, and implement service-based workflow applications.
What Are WCF Services?
WF uses the same infrastructure for handling events as it does for calling methods. It handles events in the following way:
In addition to enabling workflows to call methods on the host process, WF enables you to handle events that are raised in the host process, inside the workflow instance.
WF enables you to generate strictly bound activities to interact with methods on the host process in the same way that you create strictly bound controls. Strictly bound activities enable you to add activities to your workflow that are already configured to a specific host process event.
Windows Workflow Foundation (WF) enables you to integrate your workflow solutions seamlessly into applications that are based on the Windows operating system. The ability of the workflow to call methods in the host process and then to handle events from the host process to control execution flow is functionality that is often required.
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