Lookup<TKey, TElement>.Item Property (TKey)


Gets the collection of values indexed by the specified key.

Namespace:   System.Linq
Assembly:  System.Core (in System.Core.dll)

public IEnumerable<TElement> this[
	TKey key
] { get; }


Type: TKey

The key of the desired collection of values.

Property Value

Type: System.Collections.Generic.IEnumerable<TElement>

The collection of values indexed by the specified key.

This indexed property provides the ability to index a specific collection of values in the Lookup<TKey, TElement> by using the following syntax: myLookup[key] in Visual C# or myLookup(key) in Visual Basic. If the key is not found in the collection, an empty sequence is returned.

The following example demonstrates how to use Item to index directly into a Lookup<TKey, TElement>. This code example is part of a larger example provided for the Lookup<TKey, TElement> class.

// Select a collection of Packages by indexing directly into the Lookup.
IEnumerable<string> cgroup = lookup['C'];

Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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