Can I count properties before I create an object? In the constructor?

can I count the amount of properties in a class before I create an object? Can I do it in the constructor?

class MyClass
{  
    public string A { get; set; }
    public string B { get; set; }
    public string C { get; set; }

    public MyClass()
    {
        int count = //somehow count properties? => 3
    }
}

Thank you