Easiest Way To Make A Form Submit Without Refresh

Question

I have been trying to create a simple calculator. Using PHP I managed to get the values from input fields and jump menus from the POST, but of course the form refreshes upon submit.

Using Javascript i tried using

function changeText(){
document.getElementById('result').innerHTML = '<?php echo "$result";?>'

but this would keep giving an answer of "0" after clicking the button because it could not get values from POST as the form had not been submitted.

So I am trying to work out either the Easiest Way to do it via ajax or something similar

or to get the selected values on the jump menu's with JavaScript.

I have read some of the ajax examples online but they are quite confusing (not familiar with the language)

Answer 1

The best way to do this is with Ajax and jQuery

after you have include your jQuery library in your head, use something like the following

$('#someForm').submit(function(){
   var form = $(this);

   var serialized = form.serialize();

   $.post('ajax/register.php',{payload:serialized},function(response){
       //response is the result from the server.
       if(response)
       {
           //Place the response after the form and remove the form.
           form.after(response).remove();
       }
   });
   //Return false to prevent the page from changing.
   return false;
});

Your php would be like so.

<?php
    if($_POST)
    {
       /*
           Process data...
       */


       if($registration_ok)
       {
           echo '<div class="success">Thankyou</a>';
           die();
       }
    }
?>

Answer 2

Use jQuery + JSON combination to submit a form something like this:

test.php:

<script type="text/javascript" src="jquery-1.4.2.js"></script>
<script type="text/javascript" src="jsFile.js"></script>

<form action='_test.php' method='post' class='ajaxform'>
 <input type='text' name='txt' value='Test Text'>
 <input type='submit' value='submit'>
</form>

<div id='testDiv'>Result comes here..</div>

_test.php:

<?php
      $arr = array( 'testDiv' => $_POST['txt'] );
      echo json_encode( $arr );
?>

jsFile.js

jQuery(document).ready(function(){

    jQuery('.ajaxform').submit( function() {

        $.ajax({
            url     : $(this).attr('action'),
            type    : $(this).attr('method'),
            dataType: 'json',
            data    : $(this).serialize(),
            success : function( data ) {
                        for(var id in data) {
                            jQuery('#' + id).html( data[id] );
                        }
                      }
        });

        return false;
    });

});