FirstOrDefault< TSource >() [1/2]

static ? TSource System.Linq.ParallelEnumerable.FirstOrDefault< TSource > ( this ParallelQuery< TSource > source )

inlinestatic

Definition at line 1994 of file ParallelEnumerable.cs.

    {
        if (source == null)
        {
            throw new ArgumentNullException("source");
        }
        FirstQueryOperator<TSource> firstQueryOperator = new FirstQueryOperator<TSource>(source, null);
        QuerySettings querySettings = firstQueryOperator.SpecifiedQuerySettings.WithDefaults();
        if (firstQueryOperator.LimitsParallelism && querySettings.ExecutionMode != ParallelExecutionMode.ForceParallelism)
        {
            IEnumerable<TSource> source2 = firstQueryOperator.Child.AsSequentialQuery(querySettings.CancellationState.ExternalCancellationToken);
            IEnumerable<TSource> source3 = CancellableEnumerable.Wrap(source2, querySettings.CancellationState.ExternalCancellationToken);
            return ExceptionAggregator.WrapEnumerable(source3, querySettings.CancellationState).FirstOrDefault();
        }
        return GetOneWithPossibleDefault(firstQueryOperator, throwIfTwo: false, defaultIfEmpty: true);
    }

References System.Linq.source.