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C# C# Objects Encapsulation with Properties Computed Properties

Jamie Wyton
Jamie Wyton
3,011 Points
Posted by Jamie Wyton
Jamie Wyton
3,011 Points

setter.....?

computed properties....I just don't get this. in the video Jeremy deletes the setter to make it a computed property and says that every time the _path field is changed the property updates Location. How is this possible? I don't see any relation between the two fields in this code. In order for the property to be updated in alignment with another field surely it has to be told to do so?!

2 Answers

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

There is no longer any field associated with Location.

After the changes are made, any time Location is referenced, a call is made to GetLocationAt using _path and _pathstep. There is no longer any field or auto-property to update.

Christopher Debove
PLUS
Christopher Debove
Courses Plus Student 18,373 Points
Christopher Debove
Christopher Debove
Courses Plus Student 18,373 Points

More importantly, he did not say that the Location property would be automatically updated, but that it would always be accurate.

In fact calling the property getter Location will call GetLocationAt on the private _path field with _pathStep as argument. This is what's called a "Computed property". It computes it result from other data.