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ParallelEnumerable.LongCount<TSource> Method (ParallelQuery<TSource>)

.NET Framework (current version)

Returns an Int64 that represents the total number of elements in a parallel sequence.

Namespace:   System.Linq
Assembly:  System.Core (in System.Core.dll)

public static long LongCount<TSource>(
	this ParallelQuery<TSource> source


Type: System.Linq.ParallelQuery<TSource>

A sequence that contains elements to be counted.

Return Value

Type: System.Int64

The number of elements in the input sequence.

Type Parameters


The type of the elements of source.

Exception Condition

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


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


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


The computed result is greater than MaxValue.

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Windows Phone
Available since 8.1
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