Like many things in .NET, you have several ways of doing something with each way custom-tailored to a particular task. Using properties is one such example. You can either use CLR properties, or you can use dependency properties.

In case you are not familiar with CLR and Dependency Properties, let’s quickly look at them. The following is an example of a CLR property that you have had in .NET for a very long time:

public string AuthorName

{

get;

set;

}

Introduced as a part of WPF a few years ago and carried over to Silverlight is the new mythical bird-creature known as Dependency Properties:

public string AuthorName

{

get { return (string)GetValue(AuthorNameProperty); }

set { SetValue(AuthorNameProperty, value); }

}

 

public static readonly DependencyProperty AuthorNameProperty = DependencyProperty.Register("AuthorName", typeof(string), typeof(Page), new PropertyMetadata(""));

If you compare the Dependency Property with the CLR Property, it is quite obvious that one seems to make more sense than the other. At the very least, the CLR property seems like something you can easily remember how to write. Remembering exactly what goes into the syntax for declaring a dependency property is quite a challenge…even for seasoned WPF and Silverlight developers.

Despite the difficulty, dependency properties certainly offer more functionality than a regular CLR property. If you plan on having your property’s value be set via an animation, accessed via data binding, stored as a resource, etc., you really should take the dependency property route. You can read more about this on an article I wrote a while ago describing dependency properties inside user controls.

If you are interested in a quick pictorial overview of the difference between CLR and dependency properties, look at each property type in Expression Blend. The Properties Marker in Expression Blend for a CLR property looks as follows:

Notice that most of the commands are grayed out. Contrast this with the equivalent dependency property instead:

As you can see, you retain everything you had with CLR properties, but you also gain the ability to store the value as a resource or access the value via data binding. Not to mention, you also can animate the property very easily.

Cheers!
Kirupa