Qbservable.TakeWhile(Of TSource) Method (IQbservable(Of TSource), Expression(Of Func(Of TSource, Int32, Boolean)))

Returns values from a queryable observable sequence as long as a specified condition is true, and then skips the remaining values.

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

<ExtensionAttribute> _
Public Shared Function TakeWhile(Of TSource) ( _
	source As IQbservable(Of TSource), _
	predicate As Expression(Of Func(Of TSource, Integer, Boolean)) _
) As IQbservable(Of TSource)
Dim source As IQbservable(Of TSource)
Dim predicate As Expression(Of Func(Of TSource, Integer, Boolean))
Dim returnValue As IQbservable(Of TSource)

returnValue = source.TakeWhile(predicate)

Type Parameters


The type source.


Type: System.Reactive.Linq.IQbservable(Of TSource)
A sequence to return elements from.
Type: System.Linq.Expressions.Expression(Of Func(Of TSource, Int32, Boolean))
A function to test each source element for a condition.

Return Value

Type: System.Reactive.Linq.IQbservable(Of TSource)
A queryable 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 IQbservable(Of 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(v=vs.103).aspx or https://msdn.microsoft.com/en-us/library/bb383977(v=vs.103).aspx.