在子对象中向字典添加条目 [英] Add entry to dictionary in child object

问题描述

如何在子对象中添加条目到父对象中定义的字典？

How is it possible to add entry to dictionary, defined in parent object, from the child object?

* UPDATED
我按以下方式编辑我的配置：

*UPDATED I edit my config as follows:

<object id="ParentType" singleton="false" type="SomeType">
  <property name="FieldNameMap">
   <dictionary key-type="string"  value-type="string" >
     <entry key="Title" value="TitleName"/>     
    </dictionary>
  </property>
</object>

<object id="ChildType" singleton="false" type="SomeType" parent="ParentType">
  <property name="FieldNameMap">
   <dictionary merge="true">
     <!-- this entry should be added to, not replace the whole Dictionary -->
     <entry key="Position" value="PositionName"/>     
    </dictionary>
  </property>
</object>

但不幸的是，现在它抛出了异常：

but, unfortunately, it now throws cast exception:

无法将类型
的属性值转换为必需类型
[System.Collections.Generic.IDictionary`2 [[System.Collections.Specialized.HybridDictionary] .String，
]，[System.String，mscorlib，Version = 4.0.0.0，Culture = neutral，
PublicKeyToken = b77a5c561934e089]]

Cannot convert property value of type [System.Collections.Specialized.HybridDictionary] to required type [System.Collections.Generic.IDictionary`2[[System.String, ],[System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]]

推荐答案

我没有尝试过，但根据文档，spring.net将使用集合的添加方法添加项目，如果集合本身公开为只读属性。

I haven't tried this myself, but according to the docs, spring.net will use the Add method of the collection to add items, if the collection itself is exposed as a readonly property.

因此，可能可以使用对象定义继承来实现您描述的行为。 Config将类似于：

So it might be possible to use object definition inheritance to achieve the behavior you describe. Config will be something like:

<object id="ParentType" singleton="false" type="SomeType"
        abstract="true">
  <property name="FieldNameMap">
   <dictionary>
     <entry key="Title" value="TitleName"/>     
    </dictionary>
  </property>
</object>

<object id="ChildType" singleton="false" type="SomeType" 
        parent="ParentType">
  <property name="FieldNameMap">
   <dictionary>
     <!-- this entry should be added to, not replace the whole Dictionary -->
     <entry key="Position" value="PositionName"/>     
    </dictionary>
  </property>
</object>

这只会在 FieldNameMap readonly属性。

This will only work if FieldNameMap is a readonly property.

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