What does “=>” do in .Net C# when declaring a property? [duplicate]

Answer 1

The first uses the new-to-C#-6 expression-bodied member syntax. It's equivalent to:

public object MyObject
{
    get { return new object(); }
}

The second is also new to C# 6 - an automatically implemented read-only property. It's equivalent to:

private readonly object _myObject; // Except using an unspeakable name
public object MyObject
{
    get { return _myObject; }
}

You can only assign to MyObject from within a constructor in the declaring class, which actually just assigns to the field instead.

(Both of these "equivalencies" are using old-school property declarations, where you always have get, set or both as blocks containing code.)

Answer 2

C# 6 evaluates the expression on the right of the arrow function every time you call the property getter.

In your case, you'd instantiate a new object() every time.

In the other case, it would read from the backing field of the property.