net9.0
namespace System.Linq
{
public static class Enumerable
{
public static IEnumerable<KeyValuePair<TKey, int>>! CountBy<TSource, TKey>(this IEnumerable<TSource>! source, Func<TSource, TKey>! keySelector, IEqualityComparer<TKey>? keyComparer = null)
where TKey, notnull;
}
}
Assembly | System.Linq , Version=9.0.0.0, PublicKeyToken=b03f5f7f11d50a3a |
---|---|
Preview | The API is contained in a preview framework. |
Implementation | Source |
Help | Documentation |
.NET | 9.09.0-android9.0-ios9.0-maccatalyst9.0-macos9.0-tvos9.0-windows |
OS Platforms | For the selected framework this API is supported on all OS platforms. |