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    <p>This is a bit involved, but I'll try to explain it succinctly!</p> <p>The core idea is to start with a buffered stream of PropertyChangedEvents(PCE), but then switch to a new buffered stream every time there is a CollectionChangedEvent (CCE). Finally we merge the CCE and flattened buffered stream of PCE together.</p> <p>We start collectUpdateItems by converting the CCEs to a stream of <code>Unit.Default</code> and <code>StartWith</code> an initial value (this lets us start collecting PCEs before the first CCE). When then project (<code>Select</code>) each pulse into a new buffered stream of PCEs. The <code>Switch</code> will ensure only the most recent buffer stream is returned. The <code>Where</code> just drops empty buffers.</p> <p>Finally we <code>Merge</code> this with the original CCE stream (projected into single element lists for compatibility with the PCE buffers).</p> <p>Hope this makes sense!</p> <p>Modifying your streams slighty to start with plain, unbuffered ChangeDTO object streams:</p> <pre><code>IObservable&lt;IEnumerable&lt;ChangeDTO&gt;&gt; allItems = Observable.FromEventPattern&lt;CollectionChangedEventArgs&gt;( x =&gt; source.CollectionChanged += x, x =&gt; source.CollectionChanged-= x) .Select(i =&gt; new ChangeDTO(source.SelectedItems, true, null)}); IObservable&lt;IEnumerable&lt;ChangeDTO&gt;&gt; updatedItem = Observable.FromEventPattern&lt;PropertyChangedEventArgs&gt;( x =&gt; source.PropertyChanged += x, x =&gt; source.PropertyChanged -= x). .Select(i =&gt; new ChangeDTO(new[] {source.Item}, false, source.UpdatedProperties)); var collectUpdatedItems = allItems // We only need to know the CCE happened, not the details of it, so convert to Units .Select(_ =&gt; Unit.Default) // We must insert an event so PCEs are buffered before the first CCE .StartWith(Unit.Default) // Here we create a new PCE buffer stream at the start and after each CCE .Select(_ =&gt; updateItem.Buffer(TimeSpan.FromMilliseconds(300))) // On a CCE, switch to the new PCE buffer stream, dropping the current PCE buffer .Switch() // Finally drop any empty buffers .Where(i =&gt; i.Count &gt; 0); // merge the CollectionChangedEvents with the PropertyChangedEvent buffers return collectionUpdateItems.Merge(allItems.Select(i =&gt; new List&lt;ChangeDTO&gt; {i})); </code></pre>
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    1. POThrottle/Buffer one Observable collection based on another in Reactive Extensions
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    1. USJames World
    1. USJames World
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    1. CODid you put any of the similar code in production?
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    2. COI've not come across a need for this particular construct before; it is quite specific. I'm sure I've used similar ideas elsewhere, but none spring to mind offhand. The use of Switch is the key trick to take away from this I think.
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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