Observable.ElementAtOrDefault<TSource> Method
Returns the element at a specified index in a sequence or a default value if the index is out of range.
Namespace: System.Reactive.Linq
Assembly: System.Reactive (in System.Reactive.dll)
Syntax
'Declaration
<ExtensionAttribute> _
Public Shared Function ElementAtOrDefault(Of TSource) ( _
source As IObservable(Of TSource), _
index As Integer _
) As IObservable(Of TSource)
'Usage
Dim source As IObservable(Of TSource)
Dim index As Integer
Dim returnValue As IObservable(Of TSource)
returnValue = source.ElementAtOrDefault(index)
public static IObservable<TSource> ElementAtOrDefault<TSource>(
this IObservable<TSource> source,
int index
)
[ExtensionAttribute]
public:
generic<typename TSource>
static IObservable<TSource>^ ElementAtOrDefault(
IObservable<TSource>^ source,
int index
)
static member ElementAtOrDefault :
source:IObservable<'TSource> *
index:int -> IObservable<'TSource>
JScript does not support generic types and methods.
Type Parameters
- TSource
The type of source.
Parameters
- source
Type: System.IObservable<TSource>
The observable sequence to return the element from.
- index
Type: System.Int32
The zero-based index of the element to retrieve.
Return Value
Type: System.IObservable<TSource>
An observable sequence that produces the element at the specified position in the source sequence or a default value if the index is outside the bounds of the source sequence.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type IObservable<TSource>. When you use instance method syntax to call this method, omit the first parameter. For more information, see or .