Admin customer update data validation

[Dave224]

I would like to validate custom customer data in admin/customers.php without using javascript form validation. If the data input is bad, I want to display a message at the top of the admin customer update form page. I've set up an observer triggered by the NOTIFY_ADMIN_CUSTOMERS_UPDATE_VALIDATE notifier. If the $_POST custom data is bad, I set $error to true and added a session message to $messageStack. But the message does not display on the page that appears when the update button is clicked. You have to click the update button on that page again to get the message to appear.

Is there any way to get the message to display on the customer update form page when the update button is clicked instead of clicking update twice to get the message displayed?

Thank you!
Dave
zc157c, php 8.0.2

[lat9]

When an error is found in the admin's Customers :: Customers tool, a page-redirect doesn't occur, so you should be using $messageStack->add(), not $messageStack->add_session().

[Dave224]

When an error is found in the admin's Customers :: Customers tool, a page-redirect doesn't occur, so you should be using $messageStack->add(), not $messageStack->add_session().

Thank you, thank you, thank you!!!! Works great!
Dave224