UBlackboardComponent::GetValueAsBool

function AIModule Blueprint Since 4.0

#include "BehaviorTree/BlackboardComponent.h"

Access: public Specifiers: UFUNCTIONBlueprintCallable

Description

Returns the boolean value stored under the given blackboard key. The most common blackboard read, used to gate behavior tree branches on flags like HasLineOfSight or IsAlerted.

Caveats & Gotchas

• Returns false silently for a missing key or wrong-type key — you cannot distinguish 'false' from 'never set' or 'no such key'.
• Key lookup is by FName every call; cache the FBlackboard::FKey with GetKeyID() if you read the same key every tick from C++.
• Behavior tree decorators evaluate this same underlying value, so changing it from C++ mid-tick can immediately re-trigger decorator conditions and abort running branches.

Signature

bool GetValueAsBool(const FName& KeyName) const

Parameters

Name	Type	Description	Default
KeyName	const FName&	The name of the bool blackboard key to read.	—

Return Type

bool

Example

Gate logic on a blackboard flag C++

if (BlackboardComp->GetValueAsBool(TEXT("HasLineOfSight")))
{
    StartFiring();
}

Version History

Introduced in: 4.0

Version	Status	Notes
5.6	stable	—

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