Service feature table (no cache)
Display a feature layer from a service using the no cache feature request mode.
ServiceFeatureTable supports three request modes, which define how features are requested from the service and stored in the local table. The feature request modes have different performance characteristics. Use no cache in scenarios where you always want the freshest data.
Run the sample and pan and zoom around the map. With each interaction, new features will be requested from the service and displayed on the map.
- Set the
ServiceFeatureTable.FeatureRequestModeproperty of the service feature table to
NO_CACHEbefore the table is loaded.
- Add the table to the map using a
FeatureLayer; features will be requested for the visible extent as the user pans and zooms.
The sample uses a feature service showing pool permits for land parcels in a Riverside, CA neighborhood.
In no cache mode, features are automatically populated from the service for the visible extent. Each time the user pans and zooms, features are downloaded for the visible extent. Features are still cached in a local geodatabase for display, but the cache will always be populated with the latest data after navigation.
NOTE: No cache does not guarantee that features won't be cached locally; feature request mode is a performance concept unrelated to data security.
cache, feature request mode, performance
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