There are times when you want the users who use the class wants some kind of indication or notification when there is a change in data inside it . One of the solutions for this is to make the class implement INotifyPropertyChanged interface which is located in the namespace System.ComponentModel.

One of the primary use of the INotifyPropertyChanged is in the WPF / Silverlight / Windows Phone projects where this interface is generally used during databinding.

Below is a sample code snippet that demonstrates the usage of the INotifyPropertyChanged in C#.

How to Notify Clients when there is a change using C# ?

public class ACEmployee : INotifyPropertyChanged
 {
        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new
                PropertyChangedEventArgs(propertyName));
            }
        }
        private int _ID = 0;
        public int ID
        {
            get
            { return _ID; }
            set
            {
                _ID = value;
                OnPropertyChanged("ID");
            }
        }
 }