Creating Custom Events

How should you structure custom events for optimal performance?

class UserEvents {
  static EVENTS = {
    LOGIN: 'user:login',
    LOGOUT: 'user:logout',
    UPDATE: 'user:update'
  };
  
  static dispatch(eventName, data) {
    const event = new CustomEvent(eventName, {
      bubbles: true,
      detail: data
    });
    document.dispatchEvent(event);
  }
}

Create new event instances for each dispatch
Use event delegation and namespacing
For optimal performance with custom events: 1. Use event delegation where possible: - Attach listeners to common ancestor elements - Reduce the number of event listeners - Better memory usage 2. Implement proper event namespacing: - Organize events by feature or module - Prevent naming conflicts - Easier debugging and maintenance 3. Optimize event data: - Only include necessary data in detail - Consider data structure impact on performance 4. Use constants for event names: - Prevent typos - Enable IDE autocompletion - Make refactoring easier
Attach listeners to every element
Dispatch events to window only

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