动态得到属性的名字

class Person
{
    public int Age { get; set; }
}

class Program
{
    static void Main()
    {
        var person = new Person();
        var age = InfoOf(() => person.Age);
        Console.WriteLine(age.Name);
    }
    static PropertyInfo InfoOf<T>(Expression<Func<T>> ex)
    {
        return (PropertyInfo)((MemberExpression)ex.Body).Member;
    }
}