Visual Basic 2005 Delegates

Delegates are type-safe reference types that provide similar functions to pointers in other languages. PowerDesigner models delegates as classes with a stereotype of <<Delegate>> with a single operation code-named "<signature>". The visibility, name, comment, flags and attributes are specified on the class object whereas the return-type and parameters are specified on the operation.

You can design the following types of VB .NET delegates:

To create a delegate at the namespace level, create a class with the <<Delegate>> stereotype, and add an operation with the <<Delegate>> stereotype to this class and define a visibility for this operation. This visibility becomes the visibility of the delegate

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Public Delegate Function ActionOccurred () As Object
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To create a delegate in a class, module, or structure, you just have to create an operation with the <<Delegate>> stereotype. In the following example, class Worker is inner to module Utilities. Both contain internal delegates designed as operations with the <<Delegate>> stereotype

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Public Module Utilities
 Public Delegate Function NewWorker () As Object
 Public Class Worker
  Public Delegate Function WorkStarted () As Object
 End Class
End Module
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For information about creating and working with classes, see Classes (OOM).