Use LINQ To Filter Collection Of Nested Classes To Yield Dictionary Of Unique Properties Of Those Classes?

Jan 23, 2012

I have two classes, one nested in the other. [code]Neither "Name" or "ID" are unique between operations and records.I wish to construct a dictionary using LINQ = Dictionary(Of String, Of List(Of Integer), whereby the keys are uniqe examples of Names in my collection and the values are the collective set of distinct IDs that are associated with those names.

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Loop And Enumerate Properties Of Nested Classes In Nested Classes?

Sep 24, 2010

so far i got

code
For Each item As Reflection.FieldInfo In GetType(NameSpace.ClassWithNestedClasses).GetFields
rtfAppend(item.Name & ":" & Tab & item.GetValue(Me))
Next
For Each item As Reflection.PropertyInfo In GetType(NameSpace.ClassWithNestedClasses).GetProperties()

[code]...

which gets me the simple string vars and properties of my top class, but how can i apply this to loop through all sub classes and get there vars and props?

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[Code]....

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I have put together the following code to illustrate the problems I've been struggling with:

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[code]....

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I have created a Dictionary class (MyDictionary for the example). I am currently trying to pass MyDictionary into a function, filter it into a new instance of MyDictionary and pass this new instance into another method. When I am attempting to create the second instance from the filtered first instance of MyDictionary via Lambda Expressions and the ToDictionary Method, I am getting the following error:

Unable to cast object of type 'System.Collections.Generic.Dictionary`2[System.Int32,System.String]' to type 'MyDictionary'. I have simplified the example and recreated it in LINQPad and am getting the same error.

Here's the simplified version of my code:

[Code]...

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[code].....

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etc

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[code]....

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[Code]...

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[code]...

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[code].....

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[code]....

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public sub new()
' ???

[Code].....

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Id and Name are "primitive" types or simple types (integer and string), but Washers, represent a list of object of type "Washer", that has 3 properties:

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[code]....

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[CODE]...

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[code]....

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[Code]...

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Function GetWeldAuditInfo(ByVal ResourceId
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[CODE]...

Manager :

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[CODE]...

Salesman :

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[CODE]...

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[Code]...

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Apr 16, 2012

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Current Code

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[code]....

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So it seems that the contained Generic Dictionary is being returned as a Generic KeyValuePair when accessed via a key as opposed to iterating through the parent dictionary in a For/Each loop.

The first section of the sample works OK (using a key to access a string value in a dictionary).
The second section of the code works OK (iterating through the dictionary values in a For/Each).
The third section of the sample is where the error occurs (using a key to access a nested generic dictionary...see underlined code).

Dim td1 As Dictionary(Of String, String)
For Each thisKey As String In td1.Keys
Debug.Print(td1(thisKey))
Next
Dim td2 As Dictionary(Of String, Dictionary(Of String, String))
[Code] .....

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