Method AggregateRight

AggregateRight<TSource>(IEnumerable<TSource>, Func<TSource, TSource, TSource>)

Applies a right-associative accumulator function over a sequence. This operator is the right-associative version of the Aggregate<TSource>(IEnumerable<TSource>, Func<TSource, TSource, TSource>) LINQ operator.

Declaration

public static TSource AggregateRight<TSource>(this IEnumerable<TSource> source, Func<TSource, TSource, TSource> func)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	Source sequence.
Func<TSource, TSource, TSource>	func	A right-associative accumulator function to be invoked on each element.

Returns

Type	Description
TSource	The final accumulator value.

Type Parameters

Name	Description
TSource	The type of the elements of source.

Remarks

This operator executes immediately.

Examples

The following code example demonstrates how to collect numbers into a string using AggregateRight.

var numbers = new string[] { "1", "2", "3", "4", "5", };

// Enumerate strings from right to left and collect the text into larger strings.
var result = numbers
    .AggregateRight((a, b) => $"({a}/{b})");

Console.WriteLine(result);

// This code produces the following output:
// (1/(2/(3/(4/5))))

Exceptions

Type	Condition
ArgumentNullException	source or func is null.

AggregateRight<TSource, TAccumulate>(IEnumerable<TSource>, TAccumulate, Func<TSource, TAccumulate, TAccumulate>)

Applies a right-associative accumulator function over a sequence. The specified seed value is used as the initial accumulator value. This operator is the right-associative version of the Aggregate<TSource, TAccumulate>(IEnumerable<TSource>, TAccumulate, Func<TAccumulate, TSource, TAccumulate>) LINQ operator.

Declaration

public static TAccumulate AggregateRight<TSource, TAccumulate>(this IEnumerable<TSource> source, TAccumulate seed, Func<TSource, TAccumulate, TAccumulate> func)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	Source sequence.
TAccumulate	seed	The initial accumulator value.
Func<TSource, TAccumulate, TAccumulate>	func	A right-associative accumulator function to be invoked on each element.

Returns

Type	Description
TAccumulate	The final accumulator value.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TAccumulate	The type of the accumulator value.

Remarks

This operator executes immediately.

Examples

The following code example demonstrates how to collect numbers into a string using AggregateRight.

var numbers = new string[] { "1", "2", "3", "4", "5", };

// Enumerate strings from right to left and collect the text into larger strings.
var result = numbers
    .AggregateRight("6", (a, b) => $"({a}/{b})");

Console.WriteLine(result);

// This code produces the following output:
// (1/(2/(3/(4/(5/6)))))

Exceptions

Type	Condition
ArgumentNullException	source or func is null.

AggregateRight<TSource, TAccumulate, TResult>(IEnumerable<TSource>, TAccumulate, Func<TSource, TAccumulate, TAccumulate>, Func<TAccumulate, TResult>)

Applies a right-associative accumulator function over a sequence. The specified seed value is used as the initial accumulator value, and the resultSelector function is used to select the result value. This operator is the right-associative version of the Aggregate<TSource, TAccumulate, TResult>(IEnumerable<TSource>, TAccumulate, Func<TAccumulate, TSource, TAccumulate>, Func<TAccumulate, TResult>) LINQ operator.

Declaration

public static TResult AggregateRight<TSource, TAccumulate, TResult>(this IEnumerable<TSource> source, TAccumulate seed, Func<TSource, TAccumulate, TAccumulate> func, Func<TAccumulate, TResult> resultSelector)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	Source sequence.
TAccumulate	seed	The initial accumulator value.
Func<TSource, TAccumulate, TAccumulate>	func	A right-associative accumulator function to be invoked on each element.
Func<TAccumulate, TResult>	resultSelector	A function to transform the final accumulator value into the result value.

Returns

Type	Description
TResult	The transformed final accumulator value.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TAccumulate	The type of the accumulator value.
TResult	The type of the resulting value.

Remarks

This operator executes immediately.

Examples

The following code example demonstrates how to collect numbers into a string using AggregateRight.

var numbers = new string[] { "1", "2", "3", "4", "5", };

// Enumerate strings from right to left and collect the text into larger strings.
var result = numbers
    .AggregateRight(
        "6",
        (a, b) => $"({a}/{b})",
        s => s.Length);

Console.WriteLine(result);

// This code produces the following output:
// 21

Exceptions

Type	Condition
ArgumentNullException	source, func, or resultSelector is null.