When an action happens that causes a property to change that would not normally cause an update in the WPF controls bound to it, you raise the event and name the modified property. Once ready replace the XAML of the main window with the code below: property that combines the first and last names into a single string.The final task for the first example is to set up the Data Context for the controls.In the previous article we saw how changes in a Text Box was not immediately sent back to the source.Instead, the source was updated only after focus was lost on the Text Box.
In the Code-behind, you will find the Click handler, where we use a couple of lines of code to get the binding from the destination control and then call the Update Source() method on it.
This behavior is controlled by a property on the binding called Update Source Trigger.
It defaults to the value "Default", which basically means that the source is updated based on the property that you bind to.
For example, if a read-only property is calculated according to other, data-bound properties, controls that are linked to the calculated value will not normally update.
If the source object is updated programmatically, these changes will not normally be reported to the user interface, which will continue to show old values.
This article considers the INotify Property Changed interface, which lets classes send notifications when property values are modified.