Method Batch

Batch<TSource, TResult>(IEnumerable<TSource>, int, ReadOnlySpanFunc<TSource, TResult>)

Split the elements of a sequence into chunks of size at most size.

Declaration

public static IEnumerable<TResult> Batch<TSource, TResult>(this IEnumerable<TSource> source, int size, SuperEnumerable.ReadOnlySpanFunc<TSource, TResult> resultSelector)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	An IEnumerable<T> whose elements to chunk.
int	size	The maximum size of each chunk.
SuperEnumerable.ReadOnlySpanFunc<TSource, TResult>	resultSelector	A transform function to apply to each chunk.

Returns

Type	Description
IEnumerable<TResult>	A sequence of elements returned by resultSelector.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TResult	The type of the value return by resultSelector.

Remarks

A chunk can contain fewer elements than size, specifically the final chunk of source.

In this overload of Batch, a single array of length size is allocated as a buffer for all subsequences.

This operator uses deferred execution and streams its results.

Exceptions

Type	Condition
ArgumentNullException	source or resultSelector is null.
ArgumentOutOfRangeException	size is below 1.

Batch<TSource, TResult>(IEnumerable<TSource>, TSource[], ReadOnlySpanFunc<TSource, TResult>)

Split the elements of a sequence into chunks of size at most array.Length.

Declaration

public static IEnumerable<TResult> Batch<TSource, TResult>(this IEnumerable<TSource> source, TSource[] array, SuperEnumerable.ReadOnlySpanFunc<TSource, TResult> resultSelector)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	An IEnumerable<T> whose elements to chunk.
TSource[]	array	The array to use as a buffer for each chunk
SuperEnumerable.ReadOnlySpanFunc<TSource, TResult>	resultSelector	A transform function to apply to each chunk.

Returns

Type	Description
IEnumerable<TResult>	A sequence of elements returned by resultSelector.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TResult	The type of the value return by resultSelector.

Remarks

A chunk can contain fewer elements than array.Length, specifically the final chunk of source.

In this overload of Batch, array is used as a common buffer for all subsequences.

This operator uses deferred execution and streams its results.

Exceptions

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

Batch<TSource, TResult>(IEnumerable<TSource>, TSource[], int, ReadOnlySpanFunc<TSource, TResult>)

Split the elements of a sequence into chunks of size at most size.

Declaration

public static IEnumerable<TResult> Batch<TSource, TResult>(this IEnumerable<TSource> source, TSource[] array, int size, SuperEnumerable.ReadOnlySpanFunc<TSource, TResult> resultSelector)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	An IEnumerable<T> whose elements to chunk.
TSource[]	array	The array to use as a buffer for each chunk
int	size	The maximum size of each chunk.
SuperEnumerable.ReadOnlySpanFunc<TSource, TResult>	resultSelector	A transform function to apply to each chunk.

Returns

Type	Description
IEnumerable<TResult>	A sequence of elements returned by resultSelector.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TResult	The type of the value return by resultSelector.

Remarks

A chunk can contain fewer elements than size, specifically the final chunk of source.

In this overload of Batch, array is used as a common buffer for all subsequences. This overload is provided to ease usage of common buffers, such as those rented from ArrayPool<T>, which may return an array larger than requested.

This operator uses deferred execution and streams its results.

Exceptions

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

Batch<TSource>(IEnumerable<TSource>, int)

Split the elements of a sequence into chunks of size at most size.

Declaration

public static IEnumerable<IList<TSource>> Batch<TSource>(this IEnumerable<TSource> source, int size)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	An IEnumerable<T> whose elements to chunk.
int	size	The maximum size of each chunk.

Returns

Type	Description
IEnumerable<IList<TSource>>	An IEnumerable<T> that contains the elements the input sequence split into chunks of size size.

Type Parameters

Name	Description
TSource	The type of the elements of source.

Remarks

A chunk can contain fewer elements than size, specifically the final buffer of source.

A separate array is allocated for each returned chunk. Other overloads of Batch are available which do not require additional array allocations for each chunk.

Returned subsequences are buffered, but the overall operation is streamed.

Examples

The following code example demonstrates how to break a sequence into chunks of a specific size, using Batch.

var sequence = Enumerable.Range(1, 10);

// Break the sequence of numbers into three chunks of 3 and one chunk of 1
var result = sequence.Batch(3);

Console.WriteLine(
    "[" + 
    string.Join(
        ", ", 
        result.Select(c => "[" + string.Join(", ", c) + "]")) +
    "]");

// This code produces the following output:
// [[1, 2, 3], [4, 5, 6], [7, 8, 9], [10]]

Exceptions

Type	Condition
ArgumentNullException	source is null.
ArgumentOutOfRangeException	size is below 1.