bcquality/microsoft/knowledge/error-handling/collect-validation-errors-with-errorbehavior.md

bc-version	domain	keywords	technologies	countries	application-area
19..	error-handling	collectible-errors errorbehavior collect getcollectederrors hascollectederrors validation batch	al	w1	all

Collect validation errors with ErrorBehavior::Collect and handle the collected list

Description

By default a procedure stops on the first Error, so a user fixing ten bad rows must rerun the operation ten times. The collectible-errors feature postpones error handling to the end of the call: a procedure attributed [ErrorBehavior(ErrorBehavior::Collect)] keeps running as errors occur and gathers them, so all failures can be presented together. GetCollectedErrors() returns a List of [ErrorInfo] but does not clear the collection by default; pass true to retrieve and clear in one call, or call ClearCollectedErrors() explicitly after retrieving. This is a platform mechanism most LLMs are unaware of — they reach for a manually concatenated Text buffer or a temporary error table instead.

Best Practice

Mark the orchestrating procedure [ErrorBehavior(ErrorBehavior::Collect)] and run each item's validation so one failure doesn't abandon the rest — typically by calling the per-item routine through Codeunit.Run. When the run finishes, inspect HasCollectedErrors(), retrieve and clear the list with GetCollectedErrors(true), and fail the operation with the collected validation details. Do not replace validation failure with Message: clearing collected errors suppresses the platform failure, so the custom handler must still block the invalid operation.

See sample: collect-validation-errors-with-errorbehavior.good.al.

Anti Pattern

Three shapes signal trouble. Hand-rolled accumulation reimplements the platform feature and loses each error's ErrorInfo structure. A Collect procedure that never handles the collection falls back to the concatenated platform dialog. Finally, code that calls parameterless GetCollectedErrors(), assumes it cleared the list, and only shows a Message can both leave the errors collected and allow invalid processing to continue.

See sample: collect-validation-errors-with-errorbehavior.bad.al.