Enumerable.ExceptBy Method

Definition

Overloads

ExceptBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TKey>, Func<TSource,TKey>)

Produces the set difference of two sequences according to a specified key selector function.

ExceptBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TKey>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Produces the set difference of two sequences according to a specified key selector function.

ExceptBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TKey>, Func<TSource,TKey>)

Source:
Except.cs
Source:
Except.cs
Source:
Except.cs

Produces the set difference of two sequences according to a specified key selector function.

C#
public static System.Collections.Generic.IEnumerable<TSource> ExceptBy<TSource,TKey>(this System.Collections.Generic.IEnumerable<TSource> first, System.Collections.Generic.IEnumerable<TKey> second, Func<TSource,TKey> keySelector);

Type Parameters

TSource

The type of the elements of the input sequence.

TKey

The type of key to identify elements by.

Parameters

first
IEnumerable<TSource>

An IEnumerable<T> whose keys that are not also in second will be returned.

second
IEnumerable<TKey>

An IEnumerable<T> whose keys that also occur in the first sequence will cause those elements to be removed from the returned sequence.

keySelector
Func<TSource,TKey>

A function to extract the key for each element.

Returns

IEnumerable<TSource>

A sequence that contains the set difference of the elements of two sequences.

See also

Applies to

.NET 9 and other versions
Product Versions
.NET 6, 7, 8, 9

ExceptBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TKey>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Source:
Except.cs
Source:
Except.cs
Source:
Except.cs

Produces the set difference of two sequences according to a specified key selector function.

C#
public static System.Collections.Generic.IEnumerable<TSource> ExceptBy<TSource,TKey>(this System.Collections.Generic.IEnumerable<TSource> first, System.Collections.Generic.IEnumerable<TKey> second, Func<TSource,TKey> keySelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer);

Type Parameters

TSource

The type of the elements of the input sequence.

TKey

The type of key to identify elements by.

Parameters

first
IEnumerable<TSource>

An IEnumerable<T> whose keys that are not also in second will be returned.

second
IEnumerable<TKey>

An IEnumerable<T> whose keys that also occur in the first sequence will cause those elements to be removed from the returned sequence.

keySelector
Func<TSource,TKey>

A function to extract the key for each element.

comparer
IEqualityComparer<TKey>

The IEqualityComparer<T> to compare values.

Returns

IEnumerable<TSource>

A sequence that contains the set difference of the elements of two sequences.

See also

Applies to

.NET 9 and other versions
Product Versions
.NET 6, 7, 8, 9