Warning Messages

To help debug your client-side code, you can use the warning() method to write output to the JavaScript console of your web browser.

Use the $A.warning(string) method to write a warning message to the JavaScript console. The parameter is the message to display.

For example, $A.warning("This is a warning message."); outputs to the JavaScript console.

1This is a warning message.

$A.warning() doesn't output by default for Lightning components, which run in either PROD or PRODDEBUG modes. To log warning messages in PROD or PRODDEBUG modes, use $A.logger.subscribe("WARNING", logCustom), where logCustom() is a custom function that you define. For more information, see Logging in Production Modes.

Note

For instructions on using the JavaScript console, refer to the instructions for your web browser.

Lightning Components Developer Guide

Warning Messages