Wiley Professional Microsoft SharePoint 2007 Workflow Programming 978-0-470-40251-1 Manuale Utente

      Wor kflow Programming 

Principles          

 Business process modeling has many of the same characteristics as the traditional procedural 
programming model such as C#. However, it also exhibits characteristics that are fundamentally 
different from the traditional procedural programming model. This mismatch between the two 
models has always been the main stumbling block in workflow programming. This chapter first 
covers those characteristics that business process modeling has in common with the traditional 
procedural programming model such as C#. Then it dives into their main differences. Finally, the 
chapter discusses different types of custom activities that you can develop and shows you how to 
implement each type of custom activity.  

  Wor kflow Programming Language 

 A traditional procedural program such as a C# program consists of program statements, which are 
executed in a certain prescribed order. A business process or workflow also consists of activities 
that are executed in a certain prescribed order. For example, consider a vacation request processing 
workflow, which consists of the following activities: 

  1. 

   Employee activity:  An employee makes a vacation request.  

  2. 

   Section manager activity:  The employee ’ s section manager approves or denies the 
request.  

  3. 

   Personnel activity:  The personnel staff approves or denies the vacation request. For 
example, the personnel staff may deny the request if the employee does not have any 
more vacation days left.    

 These activities must be executed in the correct order. You wouldn ’ t want the personnel staff to 
approve the vacation request before the section manager approves it. 

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