ParallelEnumerable.TakeWhile<TSource> Method (ParallelQuery<TSource>, Func<TSource, Int32, Boolean>)
.NET Framework 4
Returns elements from a parallel sequence as long as a specified condition is true. The element's index is used in the logic of the predicate function.
Assembly: System.Core (in System.Core.dll)
public static ParallelQuery<TSource> TakeWhile<TSource>( this ParallelQuery<TSource> source, Func<TSource, int, bool> predicate )
Type Parameters
- TSource
The type of elements of source.
Parameters
- source
- Type: System.Linq.ParallelQuery<TSource>
The sequence to return elements from.
- predicate
- Type: System.Func<TSource, Int32, Boolean>
A function to test each source element for a condition; the second parameter of the function represents the index of the source element.
Return Value
Type: System.Linq.ParallelQuery<TSource>A sequence that contains 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 ParallelQuery<TSource>. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).| Exception | Condition |
|---|---|
| ArgumentNullException | source or predicate is a null reference (Nothing in Visual Basic). |
| OperationCanceledException | The query was canceled with the token passed in through WithCancellation. |
| [System.OverflowException] | More than MaxValue elements are enumerated by this query. |
| AggregateException | One or more exceptions occurred during the evaluation of the query. |
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.