Use events where appropriate
Use events where appropriate
Microsoft docsDescription
This rule detects methods that have names that ordinarily would be used for events. Events follow the Observer or Publish-Subscribe design pattern; they are used when a state change in one object must be communicated to other objects. If a method gets called in response to a clearly defined state change, the method should be invoked by an event handler. Objects that call the method should raise events instead of calling the method directly.
Some common examples of events are found in user interface applications where a user action such as clicking a button causes a segment of code to execute. The .NET event model is not limited to user interfaces. It should be used anywhere you must communicate state changes to one or more objects.
Cause
A method name begins with one of the following:
- AddOn
- RemoveOn
- Fire
- Raise
By default, this rule only looks at externally visible methods, but this is configurable.
How to fix violations
If the method is called when the state of an object changes, consider changing the design to use the .NET event model.
Example
#pragma warning disable CA1030
// The code that's violating the rule is on this line.
#pragma warning restore CA1030When to suppress
Suppress a warning from this rule if the method does not work with the .NET event model.