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Enumerable Class

NuGet: GHIElectronics.TinyCLR.Linq
Assembly: GHIElectronics.TinyCLR.Linq
Namespace: System.Linq

LINQ to Objects on top of IEnumerable{T}. Subset of the .NET BCL surface picked for embedded use - covers the common filter / project / aggregate / order / group / convert operators. Lazy operators (Where, Select, etc.) use iterator state machines; terminal operators (ToArray, Sum, OrderBy, etc.) are eager.

public static class Enumerable

Methods​

Where<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static IEnumerable<TSource> Where<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Filters a sequence of values based on a predicate.

Returns IEnumerable<TSource>

Where<TSource>(this IEnumerable<TSource> source, Func<TSource, int, bool> predicate)​

public static IEnumerable<TSource> Where<TSource>(this IEnumerable<TSource> source, Func<TSource, int, bool> predicate)

Filters a sequence of values based on a predicate that receives each element's index.

Returns IEnumerable<TSource>

OfType<TResult>(this IEnumerable source)​

public static IEnumerable<TResult> OfType<TResult>(this IEnumerable source)

Filters the elements of a sequence based on a specified type.

Returns IEnumerable<TResult>

Cast<TResult>(this IEnumerable source)​

public static IEnumerable<TResult> Cast<TResult>(this IEnumerable source)

Casts the elements of a sequence to the specified type.

Returns IEnumerable<TResult>

TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector)​

public static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector)

Projects each element of a sequence into a new form.

Returns IEnumerable<TResult> Select<TSource,

TResult>(this IEnumerable<TSource> source, Func<TSource, int, TResult> selector)​

public static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, int, TResult> selector)

Projects each element of a sequence into a new form by incorporating the element's index.

Returns IEnumerable<TResult> Select<TSource,

TResult>(this IEnumerable<TSource> source, Func<TSource, IEnumerable<TResult>> selector)​

public static IEnumerable<TResult> SelectMany<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, IEnumerable<TResult>> selector)

Projects each element of a sequence to an IEnumerable{T} and flattens the results into one sequence.

Returns IEnumerable<TResult> SelectMany<TSource,

Skip<TSource>(this IEnumerable<TSource> source, int count)​

public static IEnumerable<TSource> Skip<TSource>(this IEnumerable<TSource> source, int count)

Bypasses a specified number of elements and returns the remaining elements.

Returns IEnumerable<TSource>

Take<TSource>(this IEnumerable<TSource> source, int count)​

public static IEnumerable<TSource> Take<TSource>(this IEnumerable<TSource> source, int count)

Returns a specified number of contiguous elements from the start of a sequence.

Returns IEnumerable<TSource>

SkipWhile<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static IEnumerable<TSource> SkipWhile<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Bypasses elements while a predicate is true and returns the remaining elements.

Returns IEnumerable<TSource>

TakeWhile<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static IEnumerable<TSource> TakeWhile<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Returns elements from the start of a sequence while a predicate is true.

Returns IEnumerable<TSource>

Distinct<TSource>(this IEnumerable<TSource> source)​

public static IEnumerable<TSource> Distinct<TSource>(this IEnumerable<TSource> source)

Returns distinct elements from a sequence using the default equality comparer.

Returns IEnumerable<TSource>

Distinct<TSource>(this IEnumerable<TSource> source, IEqualityComparer<TSource> comparer)​

public static IEnumerable<TSource> Distinct<TSource>(this IEnumerable<TSource> source, IEqualityComparer<TSource> comparer)

Returns distinct elements from a sequence using a specified equality comparer.

Returns IEnumerable<TSource>

Concat<TSource>(this IEnumerable<TSource> first, IEnumerable<TSource> second)​

public static IEnumerable<TSource> Concat<TSource>(this IEnumerable<TSource> first, IEnumerable<TSource> second)

Concatenates two sequences.

Returns IEnumerable<TSource>

Reverse<TSource>(this IEnumerable<TSource> source)​

public static IEnumerable<TSource> Reverse<TSource>(this IEnumerable<TSource> source)

Inverts the order of the elements in a sequence.

Returns IEnumerable<TSource>

SequenceEqual<TSource>(this IEnumerable<TSource> first, IEnumerable<TSource> second)​

public static bool SequenceEqual<TSource>(this IEnumerable<TSource> first, IEnumerable<TSource> second)

Determines whether two sequences are equal using the default equality comparer.

Returns bool

SequenceEqual<TSource>(this IEnumerable<TSource> first, IEnumerable<TSource> second, IEqualityComparer<TSource> comparer)​

public static bool SequenceEqual<TSource>(this IEnumerable<TSource> first, IEnumerable<TSource> second, IEqualityComparer<TSource> comparer)

Determines whether two sequences are equal using a specified equality comparer.

Returns bool

Any<TSource>(this IEnumerable<TSource> source)​

public static bool Any<TSource>(this IEnumerable<TSource> source)

Determines whether a sequence contains any elements.

Returns bool

Any<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static bool Any<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Determines whether any element of a sequence satisfies a predicate.

Returns bool

All<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static bool All<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Determines whether all elements of a sequence satisfy a predicate.

Returns bool

Contains<TSource>(this IEnumerable<TSource> source, TSource value)​

public static bool Contains<TSource>(this IEnumerable<TSource> source, TSource value)

Determines whether a sequence contains a specified element using the default equality comparer.

Returns bool

Contains<TSource>(this IEnumerable<TSource> source, TSource value, IEqualityComparer<TSource> comparer)​

public static bool Contains<TSource>(this IEnumerable<TSource> source, TSource value, IEqualityComparer<TSource> comparer)

Determines whether a sequence contains a specified element using a specified equality comparer.

Returns bool

First<TSource>(this IEnumerable<TSource> source)​

public static TSource First<TSource>(this IEnumerable<TSource> source)

Returns the first element of a sequence, throwing if the sequence is empty.

Returns TSource

First<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static TSource First<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Returns the first element that satisfies a predicate, throwing if none match.

Returns TSource

FirstOrDefault<TSource>(this IEnumerable<TSource> source)​

public static TSource FirstOrDefault<TSource>(this IEnumerable<TSource> source)

Returns the first element of a sequence, or a default value if the sequence is empty.

Returns TSource

FirstOrDefault<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static TSource FirstOrDefault<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Returns the first element that satisfies a predicate, or a default value if none match.

Returns TSource

Last<TSource>(this IEnumerable<TSource> source)​

public static TSource Last<TSource>(this IEnumerable<TSource> source)

Returns the last element of a sequence, throwing if the sequence is empty.

Returns TSource

Last<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static TSource Last<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Returns the last element that satisfies a predicate, throwing if none match.

Returns TSource

LastOrDefault<TSource>(this IEnumerable<TSource> source)​

public static TSource LastOrDefault<TSource>(this IEnumerable<TSource> source)

Returns the last element of a sequence, or a default value if the sequence is empty.

Returns TSource

LastOrDefault<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static TSource LastOrDefault<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Returns the last element that satisfies a predicate, or a default value if none match.

Returns TSource

Single<TSource>(this IEnumerable<TSource> source)​

public static TSource Single<TSource>(this IEnumerable<TSource> source)

Returns the only element of a sequence, throwing if it is empty or has more than one element.

Returns TSource

Single<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static TSource Single<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Returns the only element that satisfies a predicate, throwing if none or more than one match.

Returns TSource

SingleOrDefault<TSource>(this IEnumerable<TSource> source)​

public static TSource SingleOrDefault<TSource>(this IEnumerable<TSource> source)

Returns the only element of a sequence, a default value if empty, or throws if more than one element.

Returns TSource

SingleOrDefault<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static TSource SingleOrDefault<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Returns the only element that satisfies a predicate, a default value if none match, or throws if more than one matches.

Returns TSource

ElementAt<TSource>(this IEnumerable<TSource> source, int index)​

public static TSource ElementAt<TSource>(this IEnumerable<TSource> source, int index)

Returns the element at a specified index in a sequence.

Returns TSource

ElementAtOrDefault<TSource>(this IEnumerable<TSource> source, int index)​

public static TSource ElementAtOrDefault<TSource>(this IEnumerable<TSource> source, int index)

Returns the element at a specified index, or a default value if the index is out of range.

Returns TSource

Count<TSource>(this IEnumerable<TSource> source)​

public static int Count<TSource>(this IEnumerable<TSource> source)

Returns the number of elements in a sequence.

Returns int

Count<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)​

public static int Count<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate)

Returns the number of elements in a sequence that satisfy a predicate.

Returns int

LongCount<TSource>(this IEnumerable<TSource> source)​

public static long LongCount<TSource>(this IEnumerable<TSource> source)

Returns the number of elements in a sequence as a 64-bit integer.

Returns long

Sum(this IEnumerable<int> source)​

public static int Sum(this IEnumerable<int> source)

Computes the sum of a sequence of 32-bit integers.

Returns int

Sum<TSource>(this IEnumerable<TSource> source, Func<TSource, int> selector)​

public static int Sum<TSource>(this IEnumerable<TSource> source, Func<TSource, int> selector)

Computes the sum of the 32-bit integer values selected from each element.

Returns int

Sum(this IEnumerable<long> source)​

public static long Sum(this IEnumerable<long> source)

Computes the sum of a sequence of 64-bit integers.

Returns long

Sum<TSource>(this IEnumerable<TSource> source, Func<TSource, long> selector)​

public static long Sum<TSource>(this IEnumerable<TSource> source, Func<TSource, long> selector)

Computes the sum of the 64-bit integer values selected from each element.

Returns long

Sum(this IEnumerable<double> source)​

public static double Sum(this IEnumerable<double> source)

Computes the sum of a sequence of double-precision values.

Returns double

Sum<TSource>(this IEnumerable<TSource> source, Func<TSource, double> selector)​

public static double Sum<TSource>(this IEnumerable<TSource> source, Func<TSource, double> selector)

Computes the sum of the double-precision values selected from each element.

Returns double

Sum(this IEnumerable<float> source)​

public static float Sum(this IEnumerable<float> source)

Computes the sum of a sequence of single-precision values.

Returns float

Min<TSource>(this IEnumerable<TSource> source)​

public static TSource Min<TSource>(this IEnumerable<TSource> source)

Returns the minimum value in a sequence using the default comparer.

Returns TSource

TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector)​

public static TResult Min<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector)

Returns the minimum value selected from each element of a sequence.

Returns TResult Min<TSource,

Max<TSource>(this IEnumerable<TSource> source)​

public static TSource Max<TSource>(this IEnumerable<TSource> source)

Returns the maximum value in a sequence using the default comparer.

Returns TSource

TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector)​

public static TResult Max<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector)

Returns the maximum value selected from each element of a sequence.

Returns TResult Max<TSource,

Average(this IEnumerable<int> source)​

public static double Average(this IEnumerable<int> source)

Computes the average of a sequence of 32-bit integers.

Returns double

Average(this IEnumerable<long> source)​

public static double Average(this IEnumerable<long> source)

Computes the average of a sequence of 64-bit integers.

Returns double

Average(this IEnumerable<double> source)​

public static double Average(this IEnumerable<double> source)

Computes the average of a sequence of double-precision values.

Returns double

TAccumulate>(this IEnumerable<TSource> source, TAccumulate seed, Func<TAccumulate, TSource, TAccumulate> func)​

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

Applies an accumulator function over a sequence starting from a seed value.

Returns TAccumulate Aggregate<TSource,

Aggregate<TSource>(this IEnumerable<TSource> source, Func<TSource, TSource, TSource> func)​

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

Applies an accumulator function over a sequence using the first element as the seed.

Returns TSource

TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)​

public static IOrderedEnumerable<TSource> OrderBy<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)

Sorts the elements of a sequence in ascending order by a key.

Returns IOrderedEnumerable<TSource> OrderBy<TSource,

TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, IComparer<TKey> comparer)​

public static IOrderedEnumerable<TSource> OrderBy<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, IComparer<TKey> comparer)

Sorts the elements of a sequence in ascending order by a key using a specified comparer.

Returns IOrderedEnumerable<TSource> OrderBy<TSource,

TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)​

public static IOrderedEnumerable<TSource> OrderByDescending<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)

Sorts the elements of a sequence in descending order by a key.

Returns IOrderedEnumerable<TSource> OrderByDescending<TSource,

TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, IComparer<TKey> comparer)​

public static IOrderedEnumerable<TSource> OrderByDescending<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, IComparer<TKey> comparer)

Sorts the elements of a sequence in descending order by a key using a specified comparer.

Returns IOrderedEnumerable<TSource> OrderByDescending<TSource,

TKey>(this IOrderedEnumerable<TSource> source, Func<TSource, TKey> keySelector)​

public static IOrderedEnumerable<TSource> ThenBy<TSource, TKey>(this IOrderedEnumerable<TSource> source, Func<TSource, TKey> keySelector)

Performs a subsequent ascending sort on an already ordered sequence by a key.

Returns IOrderedEnumerable<TSource> ThenBy<TSource,

TKey>(this IOrderedEnumerable<TSource> source, Func<TSource, TKey> keySelector, IComparer<TKey> comparer)​

public static IOrderedEnumerable<TSource> ThenBy<TSource, TKey>(this IOrderedEnumerable<TSource> source, Func<TSource, TKey> keySelector, IComparer<TKey> comparer)

Performs a subsequent ascending sort on an already ordered sequence by a key using a specified comparer.

Returns IOrderedEnumerable<TSource> ThenBy<TSource,

TKey>(this IOrderedEnumerable<TSource> source, Func<TSource, TKey> keySelector)​

public static IOrderedEnumerable<TSource> ThenByDescending<TSource, TKey>(this IOrderedEnumerable<TSource> source, Func<TSource, TKey> keySelector)

Performs a subsequent descending sort on an already ordered sequence by a key.

Returns IOrderedEnumerable<TSource> ThenByDescending<TSource,

TKey>(this IOrderedEnumerable<TSource> source, Func<TSource, TKey> keySelector, IComparer<TKey> comparer)​

public static IOrderedEnumerable<TSource> ThenByDescending<TSource, TKey>(this IOrderedEnumerable<TSource> source, Func<TSource, TKey> keySelector, IComparer<TKey> comparer)

Performs a subsequent descending sort on an already ordered sequence by a key using a specified comparer.

Returns IOrderedEnumerable<TSource> ThenByDescending<TSource,

TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)​

public static IEnumerable<IGrouping<TKey, TSource>> GroupBy<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)

Groups the elements of a sequence by a key.

Returns IEnumerable<IGrouping<TKey, TSource>> GroupBy<TSource,

TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, IEqualityComparer<TKey> comparer)​

public static IEnumerable<IGrouping<TKey, TSource>> GroupBy<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, IEqualityComparer<TKey> comparer)

Groups the elements of a sequence by a key using a specified equality comparer.

Returns IEnumerable<IGrouping<TKey, TSource>> GroupBy<TSource,

TElement>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector)​

public static IEnumerable<IGrouping<TKey, TElement>> GroupBy<TSource, TKey, TElement>( this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector)

Groups the elements of a sequence by a key and projects each element with an element selector.

Returns IEnumerable<IGrouping<TKey, TElement>> GroupBy<TSource, TKey,

TElement>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector, IEqualityComparer<TKey> comparer)​

public static IEnumerable<IGrouping<TKey, TElement>> GroupBy<TSource, TKey, TElement>( this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector, IEqualityComparer<TKey> comparer)

Groups the elements of a sequence by a key, projecting each element with an element selector and using a specified equality comparer.

Returns IEnumerable<IGrouping<TKey, TElement>> GroupBy<TSource, TKey,

ToArray<TSource>(this IEnumerable<TSource> source)​

public static TSource[] ToArray<TSource>(this IEnumerable<TSource> source)

Creates an array from a sequence.

Returns TSource[]

ToList<TSource>(this IEnumerable<TSource> source)​

public static List<TSource> ToList<TSource>(this IEnumerable<TSource> source)

Creates a List{T} from a sequence.

Returns List<TSource>

TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)​

public static Dictionary<TKey, TSource> ToDictionary<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)

Creates a Dictionary{TKey,TValue} from a sequence using a key selector.

Returns Dictionary<TKey, TSource> ToDictionary<TSource,

TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, IEqualityComparer<TKey> comparer)​

public static Dictionary<TKey, TSource> ToDictionary<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, IEqualityComparer<TKey> comparer)

Creates a Dictionary{TKey,TValue} from a sequence using a key selector and a specified equality comparer.

Returns Dictionary<TKey, TSource> ToDictionary<TSource,

TElement>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector)​

public static Dictionary<TKey, TElement> ToDictionary<TSource, TKey, TElement>( this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector)

Creates a Dictionary{TKey,TValue} from a sequence using key and element selectors.

Returns Dictionary<TKey, TElement> ToDictionary<TSource, TKey,

TElement>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector, IEqualityComparer<TKey> comparer)​

public static Dictionary<TKey, TElement> ToDictionary<TSource, TKey, TElement>( this IEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector, IEqualityComparer<TKey> comparer)

Creates a Dictionary{TKey,TValue} from a sequence using key and element selectors and a specified equality comparer.

Returns Dictionary<TKey, TElement> ToDictionary<TSource, TKey,

Range(int start, int count)​

public static IEnumerable<int> Range(int start, int count)

Generates a sequence of consecutive integers starting at a specified value.

Returns IEnumerable<int>

Repeat<TResult>(TResult element, int count)​

public static IEnumerable<TResult> Repeat<TResult>(TResult element, int count)

Generates a sequence that contains one repeated value.

Returns IEnumerable<TResult>

Empty<TResult>()​

public static IEnumerable<TResult> Empty<TResult>()

Returns an empty sequence of the specified type.

Returns IEnumerable<TResult>