ParallelEnumerable.SelectMany<TSource, TCollection, TResult> Method (ParallelQuery<TSource>, Func<TSource, IEnumerable<TCollection>>, Func<TSource, TCollection, TResult>)
Projects each element of a sequence to an IEnumerable<T>, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein.
Assembly: System.Core (in System.Core.dll)
public static ParallelQuery<TResult> SelectMany<TSource, TCollection, TResult>( this ParallelQuery<TSource> source, Func<TSource, IEnumerable<TCollection>> collectionSelector, Func<TSource, TCollection, TResult> resultSelector )
Parameters
- source
-
Type:
System.Linq.ParallelQuery<TSource>
A sequence of values to project.
- collectionSelector
-
Type:
System.Func<TSource, IEnumerable<TCollection>>
A transform function to apply to each source element; the second parameter of the function represents the index of the source element.
- resultSelector
-
Type:
System.Func<TSource, TCollection, TResult>
A function to create a result element from an element from the first sequence and a collection of matching elements from the second sequence.
Return Value
Type: System.Linq.ParallelQuery<TResult>A sequence whose elements are the result of invoking the one-to-many transform function collectionSelector on each element of source based on the index supplied to collectionSelector, and then mapping each of those sequence elements and their corresponding source element to a result element.
Type Parameters
- TSource
The type of the intermediate elements collected by collectionSelector.
- TCollection
The type of elements of source.
- TResult
The type of elements in the result sequence.
| Exception | Condition |
|---|---|
| ArgumentNullException | source or selector is a null reference (Nothing in Visual Basic). |
| OperationCanceledException | The query was canceled with the token passed in through WithCancellation. |
| OverflowException | More than MaxValue elements are enumerated by the query. |
| AggregateException | One or more exceptions occurred during the evaluation of the query. |
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Windows Phone
Available since 8.1