ParallelEnumerable.DefaultIfEmpty Method
Definition
Important
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Returns the elements of the specified parallel sequence or the specified value in a singleton collection if the sequence is empty.
Overloads
DefaultIfEmpty<TSource>(ParallelQuery<TSource>) |
Returns the elements of the specified parallel sequence or the type parameter's default value in a singleton collection if the sequence is empty. |
DefaultIfEmpty<TSource>(ParallelQuery<TSource>, TSource) |
Returns the elements of the specified parallel sequence or the specified value in a singleton collection if the sequence is empty. |
DefaultIfEmpty<TSource>(ParallelQuery<TSource>)
- Source:
- ParallelEnumerable.cs
- Source:
- ParallelEnumerable.cs
- Source:
- ParallelEnumerable.cs
Returns the elements of the specified parallel sequence or the type parameter's default value in a singleton collection if the sequence is empty.
public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
static System::Linq::ParallelQuery<TSource> ^ DefaultIfEmpty(System::Linq::ParallelQuery<TSource> ^ source);
public static System.Linq.ParallelQuery<TSource> DefaultIfEmpty<TSource> (this System.Linq.ParallelQuery<TSource> source);
static member DefaultIfEmpty : System.Linq.ParallelQuery<'Source> -> System.Linq.ParallelQuery<'Source>
<Extension()>
Public Function DefaultIfEmpty(Of TSource) (source As ParallelQuery(Of TSource)) As ParallelQuery(Of TSource)
Type Parameters
- TSource
The type of the elements of source
.
Parameters
- source
- ParallelQuery<TSource>
The sequence to return a default value for if it is empty.
Returns
A sequence that contains default(TSource) if source
is empty; otherwise, source
.
Exceptions
source
is a null reference (Nothing in Visual Basic).
The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).
One or more exceptions occurred during the evaluation of the query.
See also
Applies to
DefaultIfEmpty<TSource>(ParallelQuery<TSource>, TSource)
- Source:
- ParallelEnumerable.cs
- Source:
- ParallelEnumerable.cs
- Source:
- ParallelEnumerable.cs
Returns the elements of the specified parallel sequence or the specified value in a singleton collection if the sequence is empty.
public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
static System::Linq::ParallelQuery<TSource> ^ DefaultIfEmpty(System::Linq::ParallelQuery<TSource> ^ source, TSource defaultValue);
public static System.Linq.ParallelQuery<TSource> DefaultIfEmpty<TSource> (this System.Linq.ParallelQuery<TSource> source, TSource defaultValue);
static member DefaultIfEmpty : System.Linq.ParallelQuery<'Source> * 'Source -> System.Linq.ParallelQuery<'Source>
<Extension()>
Public Function DefaultIfEmpty(Of TSource) (source As ParallelQuery(Of TSource), defaultValue As TSource) As ParallelQuery(Of TSource)
Type Parameters
- TSource
The type of the elements of source
.
Parameters
- source
- ParallelQuery<TSource>
The sequence to return the specified value for if it is empty.
- defaultValue
- TSource
The value to return if the sequence is empty.
Returns
A sequence that contains defaultValue if source
is empty; otherwise, source
.
Exceptions
source
is a null reference (Nothing in Visual Basic).
The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).
One or more exceptions occurred during the evaluation of the query.