bcquality/microsoft/knowledge/events/prefer-this-over-includesender-in-codeunit-events.md
Jesper Schulz-Wedde faeacb2484 Add 12 general AL event-design articles to events domain
Add 12 atomic knowledge articles under microsoft/knowledge/events covering
general AL event-design best practices: IsHandled initialization and OnAfter
preservation, appending new event parameters, position-based event naming,
reusing/extending events, avoiding per-iteration publishing, Temp-prefixing
temporary record parameters, unabbreviated parameter names, preferring the
this keyword over IncludeSender, avoiding loosely typed parameters, not
mutating existing event contracts, and not bypassing critical operations
with IsHandled. Each article ships a .good.al and .bad.al demonstration
sample (object IDs 50240-50296; not compiled by CI). Extend the
al-events-review leaf Worklist with one targeted check per new rule.

Additive only; no contract or wiring change (events leaf already wired).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
2026-06-25 11:58:59 +02:00

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Markdown

---
bc-version: [25..]
domain: events
keywords: [this-keyword, includesender, sender, codeunit, self-reference, integration-event, type-safety]
technologies: [al]
countries: [w1]
application-area: [all]
---
# Prefer this over IncludeSender in codeunit events
## Description
Some publishers set `IncludeSender` to `true` on `[IntegrationEvent]` or `[BusinessEvent]` so subscribers receive the publishing object as an implicit sender parameter. From Business Central 2024 release wave 2, a codeunit can instead pass itself explicitly with the `this` keyword as a normal, strongly-typed `Sender` parameter. Explicit passing is clearer at both the publisher and the subscriber: the sender appears in the signature, it is concretely typed to the publishing codeunit, and it avoids the implicit-parameter mechanics of `IncludeSender`. Reserve `IncludeSender = true` for cases where the sender genuinely cannot be passed explicitly. This guidance applies to code targeting Business Central 2024 release wave 2 or later, where the `this` keyword is available.
## Best Practice
Declare the publisher `[IntegrationEvent(false, false)]` with an explicit `Sender: Codeunit "…"` parameter and raise it with `this`, for example `OnBeforeProcessOrder(OrderNo, this);`. Subscribers then receive a typed sender they can call directly.
See sample: `prefer-this-over-includesender-in-codeunit-events.good.al`.
## Anti Pattern
Relying on `[IntegrationEvent(true, …)]` solely to hand subscribers the publisher instance, where a codeunit could pass `this` explicitly as a typed parameter. Detection: `IncludeSender = true` on a codeunit event whose only purpose is to expose the sender, in code targeting Business Central 2024 release wave 2 or later.
See sample: `prefer-this-over-includesender-in-codeunit-events.bad.al`.