Validation Errors

Different validation error shapes, nested schemas, and custom error handling.

Formatted Errors (default)

Default validation error shape with nested _errors arrays.

Result:

—

Flattened Errors

Using flattenValidationErrors to get formErrors + fieldErrors shape.

Result:

—

Nested Schema

Complex nested Zod schema with superRefine producing random validation errors at different levels.

Result:

—

returnValidationErrors

Manually returning validation errors from server action code (use the formatted errors example above — try username 'johndoe').

The formatted and flattened examples above both use returnValidationErrors to manually set field-level errors from the server. Try username "johndoe" to see a user_suspended error, or any other value to see incorrect_credentials.

throwValidationErrors

Client created with throwValidationErrors: true — validation errors throw instead of returning.

Result:

—

Custom Error Shape

Using handleValidationErrorsShape to transform validation errors into a custom format.

Result:

—