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Changes API: How to subscribe to index changes?

Following methods allow you to subscribe to index changes:

ForIndex​

Index changes for one index can be observed using ForIndex method.

Syntax​

IChangesObservable<IndexChange> ForIndex(string indexName);
Parameters
indexNamestringName of an index for which notifications will be processed.
Return value
IObservableWithTask<IndexChangeNotification>Observable that allows to add subscriptions to notifications for index with given name.

Example​

IDisposable subscription = store
  .Changes()
  .ForIndex("Orders/All")
  .Subscribe(
      change =>
      {
          switch (change.Type)
          {
              case IndexChangeTypes.None:
                  //Do someting
                  break;
              case IndexChangeTypes.BatchCompleted:
                  //Do someting
                  break;
              case IndexChangeTypes.IndexAdded:
                  //Do someting
                  break;
              case IndexChangeTypes.IndexRemoved:
                  //Do someting
                  break;
              case IndexChangeTypes.IndexDemotedToIdle:
                  //Do someting
                  break;
              case IndexChangeTypes.IndexPromotedFromIdle:
                  //Do someting
                  break;
              case IndexChangeTypes.IndexDemotedToDisabled:
                  //Do someting
                  break;
              case IndexChangeTypes.IndexMarkedAsErrored:
                  //Do someting
                  break;
              case IndexChangeTypes.SideBySideReplace:
                  //Do someting
                  break;
              case IndexChangeTypes.IndexPaused:
                  //Do someting
                  break;
              case IndexChangeTypes.LockModeChanged:
                  //Do someting
                  break;
              case IndexChangeTypes.PriorityChanged:
                  //Do someting
                  break;
              default:
                  throw new ArgumentOutOfRangeException();
          }
      });

ForAllIndexes​

Index changes for all indexex can be observed using ForAllIndexes method.

Return value
IObservableWithTask<IndexChangeNotification>Observable that allows to add subscriptions to notifications for all indexes.

Syntax​

IChangesObservable<IndexChange> ForAllIndexes();

Example​

IDisposable subscription = store
  .Changes()
  .ForAllIndexes()
  .Subscribe(change => Console.WriteLine("{0} on index {1}", change.Type, change.Name));

Remarks​

To get more method overloads, especially the ones supporting delegates, please add Reactive Extensions package to your project.