ParallelEnumerable.Single Method

Definition

Namespace:

System.Linq

Assembly:

System.Linq.Parallel.dll

Returns the only element of a parallel sequence, and throws an exception if there is not exactly one element in the sequence.

Overloads

Single<TSource>(ParallelQuery<TSource>)	Returns the only element of a parallel sequence, and throws an exception if there is not exactly one element in the sequence.
Single<TSource>(ParallelQuery<TSource>, Func<TSource,Boolean>)	Returns the only element of a parallel sequence that satisfies a specified condition, and throws an exception if more than one such element exists.

Single<TSource>(ParallelQuery<TSource>)

Source:

ParallelEnumerable.cs

Returns the only element of a parallel sequence, and throws an exception if there is not exactly one element in the sequence.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static TSource Single(System::Linq::ParallelQuery<TSource> ^ source);

public static TSource Single<TSource> (this System.Linq.ParallelQuery<TSource> source);

static member Single : System.Linq.ParallelQuery<'Source> -> 'Source

<Extension()>
Public Function Single(Of TSource) (source As ParallelQuery(Of TSource)) As TSource

Type Parameters

TSource

The type of the elements of source.

Parameters

source

ParallelQuery<TSource>

The sequence to return the single element of.

Returns

TSource

The single element of the input sequence.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source is a null reference (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

InvalidOperationException

The input sequence contains more than one element. -or- The input sequence is empty.

See also

• Parallel LINQ (PLINQ)

Single<TSource>(ParallelQuery<TSource>, Func<TSource,Boolean>)

Source:

ParallelEnumerable.cs

Returns the only element of a parallel sequence that satisfies a specified condition, and throws an exception if more than one such element exists.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static TSource Single(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, bool> ^ predicate);

public static TSource Single<TSource> (this System.Linq.ParallelQuery<TSource> source, Func<TSource,bool> predicate);

static member Single : System.Linq.ParallelQuery<'Source> * Func<'Source, bool> -> 'Source

<Extension()>
Public Function Single(Of TSource) (source As ParallelQuery(Of TSource), predicate As Func(Of TSource, Boolean)) As TSource

Type Parameters

TSource

The type of the elements of source.

Parameters

source

ParallelQuery<TSource>

The sequence to return the single element of.

predicate

Func<TSource,Boolean>

A function to test an element for a condition.

Returns

TSource

The single element of the input sequence that satisfies a condition.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source or predicate is a null reference (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

InvalidOperationException

No element satisfies the condition in predicate. -or- More than one element satisfies the condition in predicate.

See also

• Parallel LINQ (PLINQ)