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Clear

procedure Clear;

Example​

procedure ResetList(const Items: TStringList);
begin
  Items.Clear;
end;

Usage​

Invokes the TStrings string list's abstract clear operation to remove every entry.

  • Treat all current indexes and entry aliases as invalid after a successful clear.
  • Do not assume associated objects are freed or retained from the TStrings type alone.
  • Clear is not rollback-safe. Event and destructor exceptions can occur after state changes.

Additional Technical Info​

Clear is declared by hidden ancestor TStrings and is normally used through a concrete visible descendant such as TStringList. The base class supplies no storage implementation, so object destruction, capacity changes and notifications are descendant-defined.

Source-backed behaviour​

TStrings.Clear is abstract. In the visible parameterless TStringList, Clear emits changing/changed notifications when nonempty, sets count to zero, releases capacity, and does not free associated objects because that construction path is non-owning. A native TStringList created with OwnsObjects=True gathers and frees its object references after detaching the array.

If an owned object's destructor raises, the list is already empty and storage released; remaining gathered objects after the failing one are not guaranteed to be freed.

Delete removes one entry. Objects explains reference ownership. Count becomes zero after a successful clear.

Official RTL references​

Created 2026-07-15