Three C# 2.0/3.0 syntaxes you didn't know but were afraid to ask

Working with other colleagues, I found these C# syntaxes are still not well known or widely used, so I thought I would blog about them.

1 – Properties Without Members

In the old days, before C# 3.0, we used to write syntax like:

public class Point {
    private int _x;
    private int _y;

    public int X {
        get {
            return _x;
        }
        set {
            _x = value;
        }
    }

    public int Y {
        get {
            return _y;
        }
        set {
            _y = value;
        }
    }
}

But if you are not doing any special processing in your property, you can use a shorter syntax introduced in C# 3.0:

public class Point {
    public int X {
        get;
        set;
    }
    public int Y {
        get;
        set;
    }
}

2 – The null-coalescing operator ??

Most of us, especially those coming from a C/C++ background, have used the ternary operator ?:, such as:

Point point1 = null;
// some code to initialize point1...
Point point2 = (point1 == null ? new Point() : point1);

C# 2.0 introduced this new syntax:

Point point1 = null;
// some code to initialize point1...
Point point2 = (point1 ?? new Point());

This does exactly the same thing as the previous syntax.

3 – Initializing Properties When Creating an Object

Point point = new Point();
point.X = 1;
point.Y = 1;

Or you can use the C# 3.0 syntax:

Point point = new Point { X = 1, Y = 1};

If you use LINQ, you have probably written code like this several times.