In the real world, the notification management system consists of two parts, one is to allow clients to subscribe/unsubscribe the notification, and the other is to facilitate administrator(s) to publish the notification. This assignment simplifies the problem and merges two parts as one. In this assignment, you are asked to implement a .NET WinForm application to mimic a notification management system. You are required to use a delegate.

Your app facilitates clients to subscribe/unsubscribe notifications as well as send notifications to all subscribers. Your App needs to make sure that the provided email address is valid and provided cell phone number is following the specified format. After the app has been launched, the following GUI (or a similar one) should be presented. As there is no subscriber when the app just launches, Publish Notification button is disabled.

Notification Manager Manage Subscription Publish Notification Exit After Manage subscription button clicked, following GUI (or similar one) should be popped up to allow clients to subscribe or unsubscribe notification. If an invalid email address has been provided, error message should be provided. Manage Notification Subscription abc@email.com Email Notification to: Text notification to TextBox Subscribe Unsubscribe Back to Main Window Manage Notifica Subscription X Email Notification to: li@hotmailcom invalide email Text notification to Subscribe Unsubscribe Back to Main Window Manage Notification Subscription - Email Notification to: li@hotmail.com Text notification to Subscribe Unsubscribe Back to Main Window After Publish Notification button clicked, following GUI is presented to facilitate notification publish. - Send Notification Notification Details: hello, this is a test notification Publish Back to Main Window Notification has been sent to following subscribers: li@hotmail.com li@gmail.com 416-345-3456 Please make sure: 1. No duplication subscription is allowed; in other words, if user tries to subscribe using the same email to subscribe again, your app should prompt warning message. 2. Your app should be able to deal with many subscribers. [hint: use collections to hold the subscribers' information] Notification Manager Manage Subscription Publish Notification Exit After Manage subscription button clicked, following GUI (or similar one) should be popped up to allow clients to subscribe or unsubscribe notification. If an invalid email address has been provided, error message should be provided. Manage Notification Subscription abc@email.com Email Notification to: Text notification to TextBox Subscribe Unsubscribe Back to Main Window Manage Notifica Subscription X Email Notification to: li@hotmailcom invalide email Text notification to Subscribe Unsubscribe Back to Main Window Manage Notification Subscription - Email Notification to: li@hotmail.com Text notification to Subscribe Unsubscribe Back to Main Window After Publish Notification button clicked, following GUI is presented to facilitate notification publish. - Send Notification Notification Details: hello, this is a test notification Publish Back to Main Window Notification has been sent to following subscribers: li@hotmail.com li@gmail.com 416-345-3456 Please make sure: 1. No duplication subscription is allowed; in other words, if user tries to subscribe using the same email to subscribe again, your app should prompt warning message. 2. Your app should be able to deal with many subscribers. [hint: use collections to hold the subscribers' information]