Observable.TakeWhile<TSource> Method (IObservable<TSource>, Func<TSource, Int32, Boolean>)
Returns values from an observable sequence as long as a specified condition is true, and then skips the remaining values.
Namespace: System.Reactive.Linq
Assembly: System.Reactive (in System.Reactive.dll)
Syntax
'Declaration
<ExtensionAttribute> _
Public Shared Function TakeWhile(Of TSource) ( _
source As IObservable(Of TSource), _
predicate As Func(Of TSource, Integer, Boolean) _
) As IObservable(Of TSource)
'Usage
Dim source As IObservable(Of TSource)
Dim predicate As Func(Of TSource, Integer, Boolean)
Dim returnValue As IObservable(Of TSource)
returnValue = source.TakeWhile(predicate)
public static IObservable<TSource> TakeWhile<TSource>(
this IObservable<TSource> source,
Func<TSource, int, bool> predicate
)
[ExtensionAttribute]
public:
generic<typename TSource>
static IObservable<TSource>^ TakeWhile(
IObservable<TSource>^ source,
Func<TSource, int, bool>^ predicate
)
static member TakeWhile :
source:IObservable<'TSource> *
predicate:Func<'TSource, int, bool> -> IObservable<'TSource>
JScript does not support generic types and methods.
Type Parameters
- TSource
The type source.
Parameters
- source
Type: System.IObservable<TSource>
A sequence to return elements from.
- predicate
Type: System.Func<TSource, Int32, Boolean>
True to the function to test each element for a condition; the second parameter of the function represents the index of the source element; otherwise, false.
Return Value
Type: System.IObservable<TSource>
An observable sequence that contains the elements from the input sequence that occur before the element at which the test no longer passes.
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 .