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IMap.PutIfAbsent(Object, Object) Method

Definition

If the specified key is not already associated with a value (or is mapped to null) associates it with the given value and returns null, else returns the current value.

[Android.Runtime.Register("putIfAbsent", "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;", "GetPutIfAbsent_Ljava_lang_Object_Ljava_lang_Object_Handler:Java.Util.IMap, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", ApiSince=24)]
public virtual Java.Lang.Object? PutIfAbsent (Java.Lang.Object? key, Java.Lang.Object? value);
[<Android.Runtime.Register("putIfAbsent", "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;", "GetPutIfAbsent_Ljava_lang_Object_Ljava_lang_Object_Handler:Java.Util.IMap, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", ApiSince=24)>]
abstract member PutIfAbsent : Java.Lang.Object * Java.Lang.Object -> Java.Lang.Object
override this.PutIfAbsent : Java.Lang.Object * Java.Lang.Object -> Java.Lang.Object

Parameters

key
Object

key with which the specified value is to be associated

value
Object

value to be associated with the specified key

Returns

the previous value associated with the specified key, or null if there was no mapping for the key. (A null return can also indicate that the map previously associated null with the key, if the implementation supports null values.)

Attributes

Remarks

If the specified key is not already associated with a value (or is mapped to null) associates it with the given value and returns null, else returns the current value.

Added in 1.8.

Java documentation for java.util.Map.putIfAbsent(K, V).

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to