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If you don’t specify a source explicitly by setting the Source property of the binding, it will inherit the Data Context from its parent element to use as its source.
In a MVVM WPF application, the view model acts as the window’s Data Context: This means that that all controls inside the window will inherit its Data Context unless some parent element of a control overrides this by setting its own Data Context property.
For example, it would be useful if the Age property of the view model was constrained to only accept values between 10 and 100 and threw an exception if the value was outside of this range: interface.
This interface defines two properties that returns a string indicating what is wrong with the object and some property of the object respectively.
A converter class converts data from one type to another during binding by implementing the Convert and Convert Back methods of the mentioned interface.
Correspondingly, an underlying data value in the view model is automatically updated when the user modifies the bound value in the view.
Provided that the view model has a property called “Name”, you bind it to a Text Box’s Text property in XAML the following way: Besides the path that specifies the name of the property to bind to, the binding must also have a source object.
This post is about how data validation works in WPF and the different validation options there are available including implementing custom Validation Rules and using the In a typical WPF application that uses the MVVM (Model-View-View Model) design pattern, a dependency property of a user interface control in a XAML-defined view uses data binding to bind to some data returned by a CLR property of the view model.
If the binding is setup correctly and the view model implements the interface to provide notifications when the data changes, the changes are automatically reflected in the elements in the view that are bound to it.