的AllowMultiple不与属性的属性工作？ [英] AllowMultiple does not work with Property Attributes?

问题描述

我绑收集所有定义属性放置在属性。有分配给属性相同类型的多个属性，但收集它们时，所得到的集合只包含特定类型的第一属性

I'm tying to collect all Custom Attributes placed over a Property. There are more than one Attributes of the same type assigned to the Property, but when collecting them , the resulting collection only contains the first Attribute of the specific type:

属性类

[AttributeUsage(System.AttributeTargets.Property,
               AllowMultiple = true)]

public class ConditionAttribute : Attribute{...}

用法：

[ConditionAttribute("Test1")]
[ConditionAttribute("Test2")]
[ConditionAttribute("Test3")]
public Color BackColor{get; set;}

现在通过对象的价值，它的类包含了道具背景色的所有道具循环时：

Now when looping through all Props of the object 'value' whose class contains the Prop "BackColor":

foreach (PropertyDescriptor property in TypeDescriptor.GetProperties(value))
{
  foreach (Attribute attribute in property.Attributes)
  {   ... }
   ....
}

集合的 property.Attributes 只包含一个属性的类型ConditionAttribute：一个与测试1。 ，而忽略其他;-(

the collection property.Attributes only contains ONE Attribute of type "ConditionAttribute" : The one with "Test1". The others are ignored;-(

因此​​，没有的AllowMultiple不行物业属性？

So does AllowMultiple not work for Property Attributes ?

在此先感谢

亨里克

推荐答案

据<一个href=\"http://social.msdn.microsoft.com/Forums/en-US/winforms/thread/e6bb4146-eb1a-4c1b-a5b1-f3528d8a7864\">a张贴在MSDN ，这是设计为的PropertyDescriptor类的一部分。

According to a post on MSDN, this is by design as part of the PropertyDescriptor class.

不过，你其实可以通过在自定义属性覆盖TYPEID解决问题（感谢伊万从思维空间中指出这一点）：

However, you can actually solve the problem by overriding TypeId in your custom attribute (Thanks to Ivan from Mindscape for pointing this out):

public override object TypeId
{
  get
  {
    return this;
  }
}

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