MoreEnumerablePairwiseTSource, TResult Method |
Returns a sequence resulting from applying a function to each
element in the source sequence and its
predecessor, with the exception of the first element which is
only returned as the predecessor of the second element.
Namespace:
MoreLinq
Assembly:
MoreLinq (in MoreLinq.dll) Version: 2.3.0
Syntax public static IEnumerable<TResult> Pairwise<TSource, TResult>(
this IEnumerable<TSource> source,
Func<TSource, TSource, TResult> resultSelector
)
<ExtensionAttribute>
Public Shared Function Pairwise(Of TSource, TResult) (
source As IEnumerable(Of TSource),
resultSelector As Func(Of TSource, TSource, TResult)
) As IEnumerable(Of TResult)
public:
[ExtensionAttribute]
generic<typename TSource, typename TResult>
static IEnumerable<TResult>^ Pairwise(
IEnumerable<TSource>^ source,
Func<TSource, TSource, TResult>^ resultSelector
)
[<ExtensionAttribute>]
static member Pairwise :
source : IEnumerable<'TSource> *
resultSelector : Func<'TSource, 'TSource, 'TResult> -> IEnumerable<'TResult>
Parameters
- source
- Type: System.Collections.GenericIEnumerableTSource
The source sequence. - resultSelector
- Type: SystemFuncTSource, TSource, TResult
A transform function to apply to
each pair of sequence.
Type Parameters
- TSource
- The type of the elements of source.
- TResult
- The type of the element of the returned sequence.
Return Value
Type:
IEnumerableTResult
Returns the resulting sequence.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type
IEnumerableTSource. 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).
Remarks
This operator uses deferred execution and streams its results.
Examples int[] numbers = { 123, 456, 789 };
IEnumerable<int> result = numbers.Pairwise((a, b) => a + b);
The
result variable, when iterated over, will yield
579 and 1245, in turn.
See Also