使用javascript刷新未设置的按钮？

Question

I am making a calculator that will display the results on the same page, but when I refresh the button is still 'set' according to php. I have a function running to catch the refresh and stop such things in javascript for something else I was doing but I am not sure how to 'un-set' the button on refresh.

<script>
document.addEventListener("DOMContentLoaded", function() {
  hide();
});
function hide() {
    var x = document.getElementById('drinksDIV');
    x.style.display = 'none';
    var x = document.getElementById('submit');
    x.session_unset;
}
function enableDisable(bEnable, textBoxID)
{
    document.getElementById(textBoxID).disabled = !bEnable
}
function myFunction() {
    var x = document.getElementById('drinksDIV');
    if (x.style.display === 'none') {
        x.style.display = 'block';
    } else {
        x.style.display = 'none';
    }
}
</script>

But when I refresh the echo'd results still remain at the top

This is what i have at the top of my page:

<?php
if(isset($_POST['submit'])){ //check if form was submitted
  $input = $_POST['age']; //get input text
  echo "Success! You entered: ".$input;
}    
?>

Once submitted once it will always be there instead of hiding on refresh

Answer 1

If you don't want anything to show on your page after your PHP code is executed, you can do this:

<?php
if(isset($_POST['submit'])){ //check if form was submitted    
  $input = $_POST['age']; //get input text
  echo "Success! You entered: ".$input;
  die();
}    
?>

Note the die() function called after the echo.