ApplyEditsAsync returns no results... sometimes...

Question

Hi,

We're building an app with Arcgis Maps SDK .Net. I can edit geometry, like move a point no problem. But when I try to create a new point using AddFeatureAsync and ApplyEditAsync sometimes it works perfectly and all of a sudden, the ApplyEdit call returns no results. No mater what when the probleme occurs it keeps happening for a long time.. Then later on I try again and it works perfectly.

I tried to diagnose the problem using Fiddler to see what is sent to the Feature Service and when no results are returned, Nothing appears in Fiddler. It's like the SDK is not sending my request at all.

Here's the code. The FeatureTable is loaded..

await ((ServiceFeatureTable)entity.Feature.FeatureTable).AddFeatureAsync(entity.Feature);
IReadOnlyList<FeatureTableEditResult> results = await ApplyEditsAsync(true);

Here results.Count = 0...

Why? How can I diagnose that further. Please help.

JenniferNery · Answer

Thanks for following-up and sharing with us the root of the problem. I am curious to know how the table was created and why ServiceGeodatabase do not see this edit.

If you loaded the feature service from a webmap or called ServiceGeodatabase.getTable() to create the ServiceFeatureTable, the ServiceFeatureTable will have a ServiceGeodatabase property. You'd see ServiceGeodatabase.connectedTables include this table. Your feature should have access to the same ServiceGeodatabase. If however, you used a ServiceFeatureTable constructor, then the table will not have a ServiceGeodatabase.

You can add a check to ServiceGeodatabase.hasLocalEdits() or ServiceFeatureTable.hasLocalEdits(), before calling the appropriate applyEdits. If this returns false, there are no edits to send to server.

It is best to use ServiceGeodatabase, for these reasons: https://developers.arcgis.com/net/edit-features/apply-edits/

if (feature.FeatureTable is ServiceFeatureTable sft && sft.ServiceGeodatabase is ServiceGeodatabase sgdb)
{
    if (sgdb.HasLocalEdits())
    {
        await sgdb.ApplyEditsAsync();
    }
}

PierreMasson · Answer

Ok I found My problem.

this:
await ((ServiceFeatureTable)entity.Feature.FeatureTable).AddFeatureAsync(entity.Feature);

is using the FeatureTable of the Feature to add the feature.

While this

((ServiceFeatureTable)this.Table).ServiceGeodatabase.ApplyEditsAsync();

uses a Reference to the table I stocked in the class doing the operation. Somewhere thing gor mixed up and it looke like it's not the same instance of the table.

so if I do AddFeatureAsync & ApplyEdits with the same table it works everytime.

Sorry this was a problem located at 18 inches from the screen.

PierreMasson · Answer

Hi,

Thank you for the suggestions. Here's the result:

* AddFeatureAsync & ApplyEditAsync are not raising any exception
* After calling AddFeatureAsync, I called getAddedFeaturesCountAsync and it returned 1 like it should.
* I added subscription to ArcGISHttpClientHandler.HttpRequestBegin & ArcGISHttpClientHandler.HttpResponseEnd before calling ApplyEditsAsync and no event are raised.

It's like ApplyEditAsync does nothing at all... The returned Result count is 0

Here's my code.

await ((ServiceFeatureTable)entity.Feature.FeatureTable).AddFeatureAsync(entity.Feature);

long numAdded = await ((ServiceFeatureTable)entity.Feature.FeatureTable).GetAddedFeaturesCountAsync();

ArcGISHttpClientHandler.HttpRequestBegin += ArcGISHttpClientHandler_HttpRequestBegin;
ArcGISHttpClientHandler.HttpResponseEnd += ArcGISHttpClientHandler_HttpResponseEnd;

IReadOnlyList<FeatureTableEditResult> results = await ((ServiceFeatureTable)this.Table).ServiceGeodatabase.ApplyEditsAsync();

ArcGISHttpClientHandler.HttpRequestBegin -= ArcGISHttpClientHandler_HttpRequestBegin;
ArcGISHttpClientHandler.HttpResponseEnd -= ArcGISHttpClientHandler_HttpResponseEnd;