Description
Appends Count new elements at the end of the array, zero-initialising their memory via FMemory::Memzero. Returns the index of the first added element. There is also a zero-parameter overload that adds a single zeroed element.
Caveats & Gotchas
- • Constructors are NOT called — this is a raw memory zero. Types with non-trivial constructors (FString, TArray, TSharedPtr) will be in an invalid state if you treat them as constructed objects without explicitly constructing them first.
- • The single-element zero-parameter overload (AddZeroed()) is separate from the counted overload. Both return the index to the first new element.
Signature
SizeType AddZeroed(SizeType Count)Parameters
| Name | Type | Description | Default |
|---|---|---|---|
| Count | SizeType | The number of zeroed elements to add. Omit or pass 1 for the single-element overload. | — |
Return Type
SizeType Example
Zero-initialise a batch of POD structs C++
struct FParticle { FVector Pos; FVector Vel; float Life; };
TArray<FParticle> Particles;
int32 StartIdx = Particles.AddZeroed(64); // 64 zeroed FParticle slots
// now safe to write into Particles[StartIdx] .. Particles[StartIdx+63]Tags
Version History
Introduced in: 4.0
| Version | Status | Notes |
|---|---|---|
| 5.6 | stable | — |
Feedback
Was this helpful?