Enumerable.CountBy<TSource,TKey> Method
Definition
Important
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Returns the count of elements in the source sequence grouped by key.
public static System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey,int>> CountBy<TSource,TKey> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector, System.Collections.Generic.IEqualityComparer<TKey>? keyComparer = default);static member CountBy : seq<'Source> * Func<'Source, 'Key> * System.Collections.Generic.IEqualityComparer<'Key> -> seq<System.Collections.Generic.KeyValuePair<'Key, int>><Extension()>
Public Function CountBy(Of TSource, TKey) (source As IEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), Optional keyComparer As IEqualityComparer(Of TKey) = Nothing) As IEnumerable(Of KeyValuePair(Of TKey, Integer))Type Parameters
- TSource
The type of elements of source.
- TKey
The type of the key returned by keySelector.
Parameters
- source
- IEnumerable<TSource>
A sequence that contains elements to be counted.
- keySelector
- Func<TSource,TKey>
A function to extract the key for each element.
- keyComparer
- IEqualityComparer<TKey>
An IEqualityComparer<T> to compare keys with.
Returns
An enumerable containing the frequencies of each key occurrence in source.
Applies to
GitHub पर हमारे साथ सहयोग करें
इस सामग्री का स्रोत GitHub पर पाया जा सकता है, जहाँ आप समस्याएँ बना और समीक्षा भी कर सकते हैं और अनुरोध खींच सकते हैं. अधिक जानकारी के लिए, हमारे योगदानकर्ता गाइड देखें.
