Generic Dictionary containing Generic Dictionary in Spring.Net

Question

I have an object that contains a property:

public Dictionary<string, Dictionary<string, List<ContextMenuItemModel>>> ContextMenuModel { get; set; }

How do I use Spring.Net to configure this property?

Answer 1

Well, configuring this in xml isn't pretty, consider switching to Spring.Net code config to configure your spring context in C#.

Anyway, to do this in xml, you use the constructors of the generic .net collections. For instance, List<T> takes an IList<T> constructor, so you can configure a list of strings as follows:

<object id="list1" type="System.Collections.Generic.List&lt;string>">
  <constructor-arg>
    <list element-type="string">
      <value>abc</value> 
      <value>def</value> 
    </list>
  </constructor-arg>
</object>

Note that in xml you have to use <, because using < isn't legal xml. Setting generic collection values is discussed in the Spring.net docs.

A generic Dictionary<string, System.Collections.Generic.List<string>> can be configured in a similar manner, which is also discussed in this answer:

<object id="dic1" type="System.Collections.Generic.Dictionary&lt;string, System.Collections.Generic.List&lt;string>>">
  <constructor-arg>
    <dictionary key-type="string" value-type="System.Collections.Generic.List&lt;string>">
      <entry key="keyToList1" value-ref="list1" />
      <entry key="keyToList2" value-ref="list2" /> 
    </dictionary>
  </constructor-arg>
</object>

And you probably see the next one coming now:

<object id="dic0" type="System.Collections.Generic.Dictionary&lt;string, System.Collections.Generic.Dictionary&lt;string, System.Collections.Generic.List&lt;string>>>">
  <constructor-arg>
    <dictionary key-type="string" value-type="System.Collections.Generic.Dictionary&lt;string, System.Collections.Generic.List&lt;string>>">
      <entry key="keyToDic1 " value-ref="dic1" />
    </dictionary>
  </constructor-arg>  
</object>

Which can be injected:

<object id="MyObject" type="MyNamespace.MyClass, MyAssembly">
  <property name="ContextMenuModel" ref="dic0" />
</object>

This isn't really pretty, but you can slightly improve the readability of your xml using type aliases.