Microsoft windows workflow foundation 4.0 cookbook
Preface 1
Chapter 1: Workflow Program 5
Introduction 5
Creating the first WF program: HelloWorkflow 6
Creating a WF program using C# Code 9
Initializing a WF program using InArguments 11
Creating a WF program using OutArgument 15
Creating a WF program using InOutArgument 17
Using Variable in a WF program 20
Running a WF program asynchronously 22
Customizing a MyReadLine activity with Bookmark 25
Converting a WF program instance to XAML 29
Loading up a WF program from an XAML file 31
Testing a WF program with a unit test framework 34
Debugging a WF program 36
Chapter 2: Built-in Flow Control Activities 41
Introduction 41
Using the Foreach activity 42
A number guessing game in Sequence 47
A number guessing game using a flowchart 49
Using the InvokeMethod activity 52
Using the Switch<T> activity in Sequence workflow 63
Using the FlowSwitch<T> activity 67
Using the Parallel activity 69
Using the ParallelForEach<T> activity 71
Using the Pick activity 73
Handling errors 78
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Table of Contents
Chapter 3: Messaging and Transaction 81
Introduction 81
Creating a pure WCF service 82
Receiving and replying to a WCF message 87
Receiving and replying to a WCF message in code workflow 92
Sending and receiving a reply to a WCF message 98
Sending and receiving a reply to a WCF message in code workflow 104
Using CancellationScope activity 108
Performing a transaction by using TransactionScope activity 112
Performing compensation by using Compensable activity 117
Performing manual compensation by using Compensate activity 120
Performing confirmation by using Confirm activity 122
Chapter 4: Manipulating Collections 125
Introduction 125
Printing collection items 125
Using AddToCollection<T> activity 130
Using ClearCollection<T> activity 133
Using RemoveFromCollection<T> activity 137
Using ExistsInCollection<T> activity 141
Chapter 5: Custom Activities 145
Introduction 145
Creating an activity by inheriting the root activity 147
Creating a FileWriter activity 150
Creating a SendEmail activity 153
Creating an Input Message activity using Bookmark 156
Creating an Asynchronous HTTP Get activity 158
Creating a Composite activity 161
Creating an Activity Designer for the SendEmail activity 164
Creating an Activity Designer for the MySquence activity 170
Chapter 6: WF4 Extensions 175
Introduction 175
Configuring ETW tracking 175
Creating FileTrackingParticipant 180
Configuring the SQL persistence store 182
Loading a persisted workflow from the database 185
Using a persistence participant to persist additional data 189
Using a customized extension 195
