PropertyChangedEventHandler and Delegates & Events in general

Question

Hi

I would just like clarification on Delegates and Events in particular the PropertyChangedEventHandler delegate. I think ive got a good grasp but I just wanted to be put right in certain places if necessary please.

// Declare PropertyChangedEventArgs which derives from the EventArgs base. This is used as it contains additional functionality instead of using the standard EventArgs.

public class PropertyChangedEventArgs : Eventargs

public PropertyChangedEventArgs(string propertyName);

public virtual string PropertyName { get; }


// Declare Delegate which takes PropertyChangedEventArgs as the 2nd parameter due to the added functionality it provides (as in the step above).

public delegate void PropertyChangedEventHandler(object sender, PropertyChangedEventArgs e)


// Declare the EventHandler with an identifer\variable named PropertyChanged.

public event PropertyChangedEventHandler PropertyChanged


// Declare a method that fires the Event which matches the signiture of the delegate and holds a reference to the EventHandler.

public void RaisePropertyChanged(string propertyName)

PropertychangedEventHandler propertyChanged = PropertyChanged;

if(propertyChanged != null)

// Not sure

propertyChanged(this, new PropertyChangedEventArgs(propertyName));

My question is how could this Event be assigned to a method I know it is subscribed by using the operator += and removed as a subscriber by -=

Thanks!