Events in Visual Basic

An event is a message sent by an object announcing that something has happened. Events are implemented using delegates, a form of object-oriented function pointer that allows a function to be invoked indirectly by way of a reference to the function.

In This Section

• Events and Event Handlers
  Provides an overview of events, event handlers, and associated terminology.

• WithEvents and the Handles Clause
  Demonstrates how to use the WithEvents keyword and the Handles clause to associate an event with an event handler.

• AddHandler and RemoveHandler
  Demonstrates how to use the AddHandler and RemoveHandler statements to dynamically associate an event with an event handler.

• How to: Add Events to a Class
  Describes the process of defining events.

• How to: Create Event Handlers in the Visual Basic Code Editor
  Gives directions for using the Visual Basic Code Editor to write code to respond to events.

• How to: Raise an Event (Visual Basic)
  Demonstrates how to define an event and uses the RaiseEvent statement to cause the event to occur

• How to: Create an Event and Handler (Visual Basic)
  Demonstrates how to define an event and an event handler, and how to use the AddHandler statement to associate them.

• How to: Write Event Handlers
  Demonstrates how to write event handlers using the Handles clause or the AddHandler statement.

• How to: Handle Events in Visual Basic
  Defines a class that raises an event when you call the CauseEvent method.

• Walkthrough: Declaring and Raising Events
  Provides a step-by-step description of how to declare and raise events for a class.

• Walkthrough: Handling Events
  Demonstrates how to write an event-handler procedure.

• How to: Declare Events That Avoid Blocking
  Demonstrates how to define a custom event that allows its event handlers to be called asynchronously.

• How to: Declare Events That Conserve Memory Use
  Demonstrates how to define a custom event that uses memory only when the event is handled.

• Troubleshooting Inherited Event Handlers in Visual Basic
  Lists common issues that arise with event handlers in inherited components.

Related Sections

• Delegates in Visual Basic
  Provides an overview of delegates in Visual Basic.

• Handling and Raising Events
  Provides an overview of the event model in the .NET Framework.

• Creating Event Handlers in Windows Forms
  Describes how to work with events associated with Windows Forms objects.