What's the benefit of private var and getter and setter over a public var?

Question

Possible Duplicate:
Why use getters and setters?

I see this a fair bit in code examples...

private List<Car> cars;

public List<Car> Cars
   {
      get { return this.cars; }
      set { this.cars = value; }
   }

What's the benefit of that over just:

public List<Car> cars;

?

Thank you.

You can add business logic to properties but for the above example where no logic is used you could use a simple public List Cars { get; set; } which will automatically generate the backing variable — Loman, Oct 26 '11 at 14:38

score 1 · Accepted Answer · answered Oct 26 '11 at 14:30

1

this is a property, a property allows you to control the set/get operations and perform other tasks when a value is set or get.

For example you could check if the cars list is null in the get and in case is null you can create and assign a new List to cars then return cars.

answered Oct 26 '11 at 14:30

Davide Piras

if you do that this could make for a nice race condition if accessed by multiple threads in parallel... – Yahia Oct 26 '11 at 14:32
@Yahia: As would exposing a field. – Adam Robinson Oct 26 '11 at 14:34
yes absolutely... I was just commenting on the example for a `get`... – Yahia Oct 26 '11 at 14:34

score 1 · Answer 2 · answered Oct 26 '11 at 14:32

1

Here are a couple of notable differences.

answered Oct 26 '11 at 14:32

JaredPar

2

Breakpoints are difficult to set on auto-properties though. – Adam Houldsworth Oct 26 '11 at 14:33
@AdamHouldsworth yes but you can always temporarily turn an auto-property into a full property for the purpose of debugging. The same is not true for fields. – JaredPar Oct 26 '11 at 14:34
definitely, I was just commenting for completion. I tend towards auto-properties / properties over public fields almost 100% of the time. Just noting because breaking an auto-property out when you are in a none standard situation (production / live code etc) is problematic. – Adam Houldsworth Oct 26 '11 at 14:35
@AdamHouldsworth: It's impossible to set a breakpoint on accessing a field (from the field side, of course), so I'm not sure how that's a distinction. – Adam Robinson Oct 26 '11 at 14:37
@AdamRobinson didn't say it was a distinction between auto-properties and fields, it was a distinction between auto-properties and properties. Auto-properties and properties are sometimes incorrectly seen as entirely synonymous, they aren't 100%. – Adam Houldsworth Oct 26 '11 at 14:38

2 Answers2