I have an add-in that queries a Feature Layer and displays results as a graphic layer. I would also like to summarize some of the returned data to display to the user. I am attempting to do sum a single field below and then display in a message box(for now). The field listed below does exist and is returned in the query and is type Double. I get the following error. Any ideas.
int Sum = featureSet.Features.Select(g => (int)g.Attributes["Cov_A"]).Sum(); MessageBox.Show (Sum.ToString());
Error occured at PolicyQuerySpatial.AddIns.QueryDialog.<QueryTask_ExecuteCompleted>b__7(Graphic g) at System.Linq.Enumerable.WhereSelectListIterator`2.MoveNext() at System.Linq.Enumerable.Sum(IEnumerable`1 source) at PolicyQuerySpatial.AddIns.QueryDialog.QueryTask_ExecuteCompleted(Object sender, QueryEventArgs args) at ESRI.ArcGIS.Client.Tasks.QueryTask.OnExecuteCompleted(QueryEventArgs args) at ESRI.ArcGIS.Client.Tasks.QueryTask.<>c__DisplayClass6.<request_Completed>b__4(FeatureSet fs, Exception ex) at ESRI.ArcGIS.Client.Tasks.FeatureSet.<>c__DisplayClass2.<FromJsonAsync>b__0(Object s, RunWorkerCompletedEventArgs e) at System.ComponentModel.BackgroundWorker.OnRunWorkerCompleted(RunWorkerCompletedEventArgs e) at System.ComponentModel.BackgroundWorker.<OnRun>b__1(Object state)
