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ParallelEnumerable.LastOrDefault Method

  • Reference

Definition

Namespace:
System.Linq
Assembly:
System.Linq.Parallel.dll
Assembly:
System.Core.dll
Assembly:
netstandard.dll

Returns the last element of a parallel sequence, or a default value if the sequence contains no elements.

Overloads

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

Returns the last element of a parallel sequence that satisfies a condition, or a default value if no such element is found.
LastOrDefault<TSource>(ParallelQuery<TSource>)

Returns the last element of a parallel sequence, or a default value if the sequence contains no elements.

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

Source:
ParallelEnumerable.cs
Source:
ParallelEnumerable.cs
Source:
ParallelEnumerable.cs

Returns the last element of a parallel sequence that satisfies a condition, or a default value if no such element is found.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static TSource LastOrDefault(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, bool> ^ predicate);
public static TSource LastOrDefault<TSource> (this System.Linq.ParallelQuery<TSource> source, Func<TSource,bool> predicate);
public static TSource? LastOrDefault<TSource> (this System.Linq.ParallelQuery<TSource> source, Func<TSource,bool> predicate);
static member LastOrDefault : System.Linq.ParallelQuery<'Source> * Func<'Source, bool> -> 'Source
<Extension()>
Public Function LastOrDefault(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 an element from.

predicate
Func<TSource,Boolean>

A function to test each element for a condition.

Returns

TSource

default() if the sequence is empty or if no elements pass the test in the predicate function; otherwise, the last element that passes the test in the predicate function.

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.

Remarks

If the query is not ordered, then the last element is non-deterministic. For more information, see Order Preservation in PLINQ.

See also

Applies to

LastOrDefault<TSource>(ParallelQuery<TSource>)

Source:
ParallelEnumerable.cs
Source:
ParallelEnumerable.cs
Source:
ParallelEnumerable.cs

Returns the last element of a parallel sequence, or a default value if the sequence contains no elements.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static TSource LastOrDefault(System::Linq::ParallelQuery<TSource> ^ source);
public static TSource LastOrDefault<TSource> (this System.Linq.ParallelQuery<TSource> source);
public static TSource? LastOrDefault<TSource> (this System.Linq.ParallelQuery<TSource> source);
static member LastOrDefault : System.Linq.ParallelQuery<'Source> -> 'Source
<Extension()>
Public Function LastOrDefault(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 an element from.

Returns

TSource

default() if the source sequence is empty; otherwise, the last element in the 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.

Remarks

If the query is not ordered, then the last element is non-deterministic. For more information, see Order Preservation in PLINQ.

See also

Applies to