Do C# properties hide instance variables or is something deeper going on?

.net, c#

Solution

You return a new object on each access to the property and that is not the expected behavior of properties. Instead you should return the same value each time (e.g. a value stored in a field). A property getter is simply glorified syntax for a method that returns a value. Your code compiles into something like this (the compiler creates a getter by prefixing the property name with `get_` which is then emitted as IL):

public class foo
{
    public object get_newObject()
    {
        return new object();
    }
}

Each call to the getter will create a new object that `foo` doesn't know about or has access to.

Does this therefore mean that at some point in time the value of the newObject property has a reference to the returned new object?

No.

Property using a backing field:

class Foo {

  readonly Object bar = new Object();

  public Object Bar { get { return this.bar; } }

}

Using automatic properties:

class Foo {

  public Foo() {
    Bar = new Object();
  }

  public Object Bar { get; private set; }

}

A property is accessed using the same easy syntax as a public field. However, by using a property you can add code to the getter and the setter allowing you to do stuff like lazy loading in the getter or validation in the setter (and much more).

Problem

Consider the class: ``` public class foo { public object newObject { get { return new object(); } } } ``` According to MSDN: Properties are members that provide a flexible mechanism to read, write, or compute the values of private fields. Properties can be used as though they are public data members, but they are actually special methods called accessors. This enables data to be accessed easily And: Properties enable a class to expose a public way of getting and setting values, while hiding implementation or verification code. A get property accessor is used to return the property value, and a set accessor is used to assign a new value. These accessors can have different access levels. For more information, see Accessor Accessibility. The value keyword is used to define the value being assigned by the set indexer. Properties that do not implement a set method are read only. while still providing the safety and flexibility of methods. Does this therefore mean that at some point in time the value of the newObject property has a reference to the returned new object? edit removed readonly from property edit2 also would like to clarify that this is not the best use for a property but its done to try and illustrate the question more effectively.

Original source