TArray::Add

function Core Since unknown

#include "Containers/Array.h"

Access: public

Description

Appends an element to the end of the array and returns its index. Both copy and move overloads exist.

Signature

UE_FORCEINLINE_HINT SizeType Add(ElementType&& Item)

Parameters

Name	Type	Description	Default
Item	ElementType&&	The element to append. Accepts both lvalue (copy) and rvalue (move) overloads.	—

Return Type

int32

Caveats & Gotchas

• Returns the index of the newly added element, not a bool. This is a common source of confusion when porting from std::vector::push_back.
• May trigger a reallocation if the array exceeds its current capacity. Call Reserve() upfront when the final size is known to avoid repeated allocations.
• For constructing an element in-place without a temporary, prefer Emplace() — it forwards constructor arguments directly and avoids a copy/move.

Example

Build a list of targets and use the returned index C++

TArray<AActor*> Targets;
Targets.Reserve(10);

for (AActor* Actor : AllActors)
{
	if (IsValidTarget(Actor))
	{
		int32 Index = Targets.Add(Actor);
		UE_LOG(LogTemp, Log, TEXT("Added target at index %d"), Index);
	}
}

Version History

Introduced in: unknown

Version	Status	Notes
5.6	stable	—

Feedback

Was this helpful?