ftIDispatch

ftIDispatch = 34

Example

function IsAutomationReference(Field: TField): Boolean;
begin
  Result := Field.DataType = ftIDispatch;
end;

Usage

ftIDispatch identifies an Automation IDispatch interface reference with COM lifetime, apartment and invocation constraints.

Additional Technical Info

ftIDispatch is ordinal 34 of TFieldType. Delphi maps it to TIDispatchField, an TInterfaceField descendant holding an Automation IDispatch reference.

This is a live COM interface, not serialized business data. Reference counting governs lifetime, while COM apartment/threading rules govern where it can be invoked. The enum does not prove that a method/property exists or that late-bound calls are safe. Validate the expected automation contract and release references promptly.

Do not retain the reference beyond its dataset/host context, marshal it across threads without COM support, or invoke untrusted automation objects. Null/nil remains distinct from an object whose method returns Empty or Null.

The example only inspects metadata and was source-reviewed; no COM creation/invocation, interface, dataset, runtime or image test ran.

External references

• Embarcadero TFieldType, TIDispatchField and IDispatch.
• Free Pascal TFieldType compatibility reference; COM behavior is platform/runtime specific.

Created 2026-07-15