ParallelEnumerable.First<TSource> Method (ParallelQuery<TSource>, Func<TSource, Boolean>)
Returns the first element in a parallel sequence that satisfies a specified condition.
Assembly: System.Core (in System.Core.dll)
public static TSource First<TSource>( this ParallelQuery<TSource> source, Func<TSource, bool> predicate )
The type of the elements of source.
- Type: System.Linq.ParallelQuery<>
The sequence to return an element from.
The first element in the sequence that passes the test in the specified predicate function.
Usage NoteIn Visual Basic and C#, you can call this method as an instance method on any object of type ParallelQuery<>. 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).
The query was canceled with the token passed in through WithCancellation.
source or predicate is a null reference (Nothing in Visual Basic).
One or more exceptions occurred during the evaluation of the query.
No element in source satisfies the condition in predicate.
If the query is not ordered, then the first element is non-deterministic. For more information, see Order Preservation in PLINQ.