Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All

ParallelEnumerable.LongCount(Of TSource) Method (ParallelQuery(Of TSource), Func(Of TSource, Boolean))

Returns an Int64 that represents how many elements in a parallel sequence satisfy a condition.

Namespace:  System.Linq
Assemblies:   System.Linq.Parallel (in System.Linq.Parallel.dll)
  System.Core (in System.Core.dll)

'Declaration
<ExtensionAttribute> _
Public Shared Function LongCount(Of TSource) ( _
	source As ParallelQuery(Of TSource), _
	predicate As Func(Of TSource, Boolean) _
) As Long

Type Parameters

TSource

The type of the elements of source.

Parameters

source
Type: System.Linq.ParallelQuery(Of TSource)

A sequence that contains elements to be counted.

predicate
Type: System.Func(Of TSource, Boolean)

A function to test each element for a condition.

Return Value

Type: System.Int64
A number that represents how many elements in the sequence satisfy the condition in the predicate function.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type ParallelQuery(Of TSource). When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

ExceptionCondition
OperationCanceledException

The query was canceled with the token passed in through WithCancellation.

ArgumentNullException

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

AggregateException

The number of elements in source is larger than MaxValue. -or- One or more exceptions occurred during the evaluation of the query.

OverflowException

The computed result is greater than MaxValue.

.NET Framework

Supported in: 4.6, 4.5, 4

.NET Framework Client Profile

Supported in: 4

.NET for Windows Phone apps

Supported in: Windows Phone 8.1

Portable Class Library

Supported in: Portable Class Library
Show:
© 2015 Microsoft