property 与 attribute 的区别？

一个是属性，用于存取类的字段，一个是特性，用来标识类，方法等的附加性质。

属性：

class TimePeriod
{
    private double seconds;

    public double Hours
    {
        get { return seconds / 3600; }
        set { seconds = value * 3600; }
    }
}

class Program
{
    static void Main()
    {
        TimePeriod t = new TimePeriod();

        // Assigning the Hours property causes the ‘set‘ accessor to be called.
        t.Hours = 24;

        // Evaluating the Hours property causes the ‘get‘ accessor to be called.
        System.Console.WriteLine("Time in hours: " + t.Hours);
    }
}
// Output: Time in hours: 24

特性：

using System;
using System.Reflection;

namespace CustomAttrCS
{
    // An enumeration of animals. Start at 1 (0 = uninitialized).
    public enum Animal
    {
        // Pets.
        Dog = 1,
        Cat,
        Bird,
    }

    // A custom attribute to allow a target to have a pet.
    public class AnimalTypeAttribute : Attribute
    {
        // The constructor is called when the attribute is set.
        public AnimalTypeAttribute(Animal pet)
        {
            thePet = pet;
        }

        // Keep a variable internally ...
        protected Animal thePet;

        // .. and show a copy to the outside world.
        public Animal Pet
        {
            get { return thePet; }
            set { thePet = Pet; }
        }
    }

    // A test class where each method has its own pet.
    class AnimalTypeTestClass
    {
        [AnimalType(Animal.Dog)]
        public void DogMethod() { }

        [AnimalType(Animal.Cat)]
        public void CatMethod() { }

        [AnimalType(Animal.Bird)]
        public void BirdMethod() { }
    }

    class DemoClass
    {
        static void Main(string[] args)
        {
            AnimalTypeTestClass testClass = new AnimalTypeTestClass();
            Type type = testClass.GetType();
            // Iterate through all the methods of the class.
            foreach (MethodInfo mInfo in type.GetMethods())
            {
                // Iterate through all the Attributes for each method.
                foreach (Attribute attr in
                    Attribute.GetCustomAttributes(mInfo))
                {
                    // Check for the AnimalType attribute.
                    if (attr.GetType() == typeof(AnimalTypeAttribute))
                        Console.WriteLine(
                            "Method {0} has a pet {1} attribute.",
                            mInfo.Name, ((AnimalTypeAttribute)attr).Pet);
                }
            }
        }
    }
}

/*
 * Output:
 * Method DogMethod has a pet Dog attribute.
 * Method CatMethod has a pet Cat attribute.
 * Method BirdMethod has a pet Bird attribute.
 */