IReadOnlyDictionary<TKey, TValue>::Item Property (TKey)

.NET Framework (current version)

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Gets the element that has the specified key in the read-only dictionary.

Namespace:   System.Collections.Generic
Assembly:  mscorlib (in mscorlib.dll)

property TValue default[
	TKey key
] {
	TValue get(TKey key);


Type: TKey

The key to locate.

Property Value

Type: TValue

The element that has the specified key in the read-only dictionary.

Exception Condition

key is null.


The property is retrieved and key is not found.

This property lets you access a specific element in the collection by using the following syntax: myCollection[key] (myCollection(key) in Visual Basic).

Implementations can vary in how they determine the equality of objects: for example, the class that implements IReadOnlyDictionary<TKey, TValue> might use the Comparer<T>::Default property, or it might implement the IComparer<T> method.

Implementations can vary in whether they allow key to be null.

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.5
Portable Class Library
Supported in: portable .NET platforms
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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