I need to press a specific button which open a pop up form automatically

[havealot]

Hello guys , as said in the title , I'm working on a website as a developer using PHP , what I have now is a pop up review form , which appears when the user press a button, the problem is I'm validating it using PHP and when you press on the submit the validation occurs server side as you know and when it loads the page again you have you will find the form is gone , and you have to press that button again to see the result of the validation
like: "please enter a valid email..", is there any way I could press that button automatically if isset($_POST) or something ?

I can provide you with a link of the website if it is allowed , just tell me if you need it.

I need help :\
thanks in advance

[Dormilich]

when you press on the submit the validation occurs server side as you know and when it loads the page again you have you will find the form is gone

when you’re doing the validation and you build up the response, you need to make sure the form is there (in the HTML), visible (via CSS), validated (showing any error messages). therefore PHP needs to fill in the received input data back into the form.

you also might have a look like frameworks (Symfony, Laravel, Zend) do their form handling.

[Bharat383]

you can use the jquery trigger for the same.
when the page reload with the error, you can check run that code as below :

<?php
if(isset($_SESSION['error'])
{
?><script type="text/javascript">$( "#button_to_show_popup" ).trigger( "click" );</script><?php
}

?>