# 释义

本不属于某个对象的属性，在被需要的时候后来附加;在特定环境下，对象才具有的属性，如当一个控件在Grid中时，会附加Grid.Column属性等

本质上是依赖属性
用clr属性包装时不同，是采用两个方法

```csharp
public static int GetMyProperty(DependencyObject obj)
        {
            return (int)obj.GetValue(MyPropertyProperty);
        }

        public static void SetMyProperty(DependencyObject obj, int value)
        {
            obj.SetValue(MyPropertyProperty, value);
        }

        // Using a DependencyProperty as the backing store for MyProperty.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty MyPropertyProperty =
            DependencyProperty.RegisterAttached("MyProperty", typeof(int), typeof(ownerclass), new PropertyMetadata(0));
```

把年级附加属性附加给人

```csharp
class Human:DependencyObject
{

}
Human human=new Human()
School.SetMyProperty(human,6)//设置属性
int grade=School.GetMyProperty(human)//得到属性值
```