The most secure trigger is Currant page submit.
if you have more than one form on the page however, you will need to use the Button XYZ Pressed trigger.
the triggers are just If statements, so you can modify them to suit you needs.
You could add an additional if statement around a code block using the button xyz pressed trigger to also include the currant page submit trigger. For example, ther button pressed trigger may look like:
<?php
if (isset($_POST["Submit_order"]))
{
<some code>
}
?>
to add the currant page submit trigger to that:
<?php if (($_SERVER["REQUEST_METHOD"] == "POST") && (isset($_SERVER["HTTP_REFERER"]) && strpos(urldecode($_SERVER["HTTP_REFERER"]), urldecode($_SERVER["SERVER_NAME"].$_SERVER["PHP_SELF"])) > 0) && isset($_POST)) { ?>
<?php
if (isset($_POST["Submit_order"]))
{
<some code>
}
?>
<?php } ?>