IReadOnlyDictionary<'TKey, 'TValue>.ContainsKey Method ('TKey)

.NET Framework (current version)
 

Determines whether the read-only dictionary contains an element that has the specified key.

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

abstract ContainsKey : 
        key:'TKey -> bool

Parameters

key
Type: TKey

The key to locate.

Return Value

Type: System.Boolean

true if the read-only dictionary contains an element that has the specified key; otherwise, false.

Exception Condition
ArgumentNullException

key is null.

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
Return to top
Show: