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Observable.First(TSource) Method (IObservable(TSource))

Returns the first element of an observable sequence with a specified source.

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

JScript does not support generic types and methods.

Type Parameters

TSource

The type of source.

Parameters

source
Type: System.IObservable(TSource)
The source observable sequence.

Return Value

Type: TSource
The first element in the observable 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 https://msdn.microsoft.com/en-us/library/bb384936.aspx or https://msdn.microsoft.com/en-us/library/bb383977.aspx.
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