XComparerThenByT, TKey Method

Chains a secondary comparer with ascending order based on the specified key to an existing comparer.

Namespace: Linq.Extras
Assembly: Linq.Extras (in Linq.Extras.dll) Version: 5.0.0+96a4f4bfed64095342c5df107c1fe1fb95603ee5

Syntax

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public static IComparer<T> ThenBy<T, TKey>(
	this IComparer<T> comparer,
	Func<T, TKey> keySelector,
	IComparer<TKey>? keyComparer = null
)

<ExtensionAttribute>
Public Shared Function ThenBy(Of T, TKey) ( 
	comparer As IComparer(Of T),
	keySelector As Func(Of T, TKey),
	Optional keyComparer As IComparer(Of TKey) = Nothing
) As IComparer(Of T)

[<ExtensionAttribute>]
static member ThenBy : 
        comparer : IComparer<'T> * 
        keySelector : Func<'T, 'TKey> * 
        ?keyComparer : IComparer<'TKey> 
(* Defaults:
        let _keyComparer = defaultArg keyComparer null
*)
-> IComparer<'T>

Parameters

comparer: Type: System.Collections.GenericIComparerT
The primary comparer.
keySelector: Type: SystemFuncT, TKey
A function that returns the comparison key.
keyComparer (Optional): Type: System.Collections.GenericIComparerTKey
An optional comparer used to compare the keys.

Type Parameters

T: The type of the objects to compare.
TKey: The type of the comparison key.

Return Value

Type: IComparerT
A comparer that will use the primary comparer, then the secondary comparer if necessary.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IComparerT. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

Reference

XComparer Class