API Reference > ecschema-metadata > Diagnostic > createSchemaItemDiagnosticClass createSchemaItemDiagnosticClass Function Deprecated Moved to the ecschema-editing package. Beta Helper method for creating SchemaItemDiagnostic child classes. createSchemaItemDiagnosticClass<ITEM extends SchemaItem<ITEM>, ARGS extends any[]>(code: string, messageText: string): undefined Parameter Type Description code string The string that uniquely identifies the diagnostic in the format ':'. messageText string The message to associate with the diagnostic class. Defined in core/ecschema-metadata/src/Validation/Diagnostic.ts Line 278 Last Updated: 29 November, 2022