【C#】nullチェックを楽にする演算子のオーバーロード ref: http://qiita.com/iwashihead/items/7757003712b64a1f6fa8

file0.cs

public class Hoge
{
    public static implicit operator bool(Hoge self)
    {
        return self != null;
    }

    public static bool operator true(Hoge self)
    {
        return self != null;
    }

    public static bool operator false(Hoge self)
    {
        return self == null;
    }
}

file1.cs

public class Main
{
    private Hoge hoge;

    public Main(object[] args)
    {
        if (hoge) { Console.WriteLine(hoge.ToString()); }
    }
}