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POCollection as key in Dictionary
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  1. POCollection as key in Dictionary
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    copied!<p>I have a dictionary like this:</p> <pre><code>var dic = Dictionary&lt;Collection&lt;MyObject&gt;, string&gt; </code></pre> <p>Then I add an entry like this:</p> <pre><code>dic.Add(myObjColl, "1"); </code></pre> <p>where myObjColl contains a single entry</p> <p>On the second run I try to add another entry to dic where myObjColl has two entries (one of them the same as the one in the first run) and I get an exception that the key already exists.</p> <p>What am I missing here? I expect the dictionary key to be a collection and surely two collections with different number of entries cannot be identical.</p> <p>EDIT: What happened was that myObjColl was initialized outside a foreach and during the second iteration updated. So what I thought was a NEW collection with two entries was actually the old one entry collection with an additional entry added.</p> <p>To elaborate a bit on my issue:</p> <p>I have a collection of product row objects. Each with a product identification object consisting of a collection of key value pairs:</p> <pre><code>Collection&lt;ProductKeyValuePair&gt; productIdentification; myProductRow.ProductIdentification = productIdentification; </code></pre> <p>I then have to construct another collection of ProductKeyValuePairs defining the "owner" of each product row object (one product row object can have multiple owners) and I need to add each owner to the correspoding procuct row object(s). A traditional many to many where the common key is a collection of KeyValuePairs.</p> <p>Hard to explain but it's really down to legacy data returned from old systems running on a mainframe and most likely stored in a hierarchical database of some sort :-/</p>
 

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