ExperimentalEnumerableTrySingleT, TCardinality, TResult Method (IEnumerableT, TCardinality, TCardinality, TCardinality, FuncTCardinality, T, TResult)

public static TResult TrySingle<T, TCardinality, TResult>(
	this IEnumerable<T> source,
	TCardinality zero,
	TCardinality one,
	TCardinality many,
	Func<TCardinality, T, TResult> resultSelector
)

<ExtensionAttribute>
Public Shared Function TrySingle(Of T, TCardinality, TResult) ( 
	source As IEnumerable(Of T),
	zero As TCardinality,
	one As TCardinality,
	many As TCardinality,
	resultSelector As Func(Of TCardinality, T, TResult)
) As TResult

public:
[ExtensionAttribute]
generic<typename T, typename TCardinality, typename TResult>
static TResult TrySingle(
	IEnumerable<T>^ source, 
	TCardinality zero, 
	TCardinality one, 
	TCardinality many, 
	Func<TCardinality, T, TResult>^ resultSelector
)

[<ExtensionAttribute>]
static member TrySingle : 
        source : IEnumerable<'T> * 
        zero : 'TCardinality * 
        one : 'TCardinality * 
        many : 'TCardinality * 
        resultSelector : Func<'TCardinality, 'T, 'TResult> -> 'TResult 

Parameters

source

Type: System.Collections.GenericIEnumerableT
The source sequence.

zero

Type: TCardinality
The value that is passed as the first argument to resultSelector if the sequence has zero elements.

one

Type: TCardinality
The value that is passed as the first argument to resultSelector if the sequence has a single element only.

many

Type: TCardinality
The value that is passed as the first argument to resultSelector if the sequence has two or more elements.

resultSelector

Type: SystemFuncTCardinality, T, TResult
A function that receives the cardinality and, if the sequence has just one element, the value of that element as argument and projects a resulting value of type TResult.

Type Parameters

T

The type of the elements of source.

TCardinality

The type that expresses cardinality.

TResult

The type of the result value returned by the resultSelector function.

Return Value

Usage Note

Reference