Form submit button not passing name to php - php

Question

Probably a very simple answer but one I am struggling with. I have a basic form which has a standard submit button. When this is clicked, it is being valued by jquery serialize and then Ajax to process php page etc. I am confused as to why the name of my submit button 'submit' is not being posted when a user clicks on it. The only reason I can think of, is that serialize only handles text,text area and select elements. If so, how can I send the name through to php for processing. I have included some sample code and would be grateful if someone could point me in the right direction. Thanks
html form
<!--- Form to add box -->
<div id="boxaddform" style="display:none;">
<div class="dialogTop_padd"></div>
<form id="BA_boxform" name="BA_boxform" method="post">
<fieldset>
<legend><span></span>Select Company</legend>
<div class="spacer"></div>
<div class="formMessage">Click again to open</div>
<div class="fld_fld">
<div>
<label for="BA_customer">Company:</label><br />
<select name="BA_customer" id="BA_customer">
<option SELECTED VALUE="">Select a Company</option>
<?php
do {
?>
<option value="<?php echo $row_Recordsetcust['customer']?>"><?php echo $row_Recordsetcust['customer']?></option>
<?php
}
while ($row_Recordsetcust = mysql_fetch_assoc($Recordsetcust));
$rows = mysql_num_rows($Recordsetcust);
if($rows > 0)
{
mysql_data_seek($Recordsetcust, 0);
$row_Recordsetcust = mysql_fetch_assoc($Recordsetcust);
}
?>
</select>
<div class="spacer"></div>
<!--- displays the address and dept from the change function -->
<div id="BA_dept"></div>
<br />
<div id="BA_address"></div>
</div>
</fieldset>
<div class="dialogTop_padd"></div>
<!--- fieldset for service level -->
<fieldset>
<legend>Service Level</legend>
<div class="spacer"></div>
<div>
<label for="BA_service">Service level:</label>
<select name="BA_service" id="BA_service">
<option SELECTED VALUE="">Select an option</option>
<option value="Standard">Standard</option>
<option value="Rapid">Rapid</option>
</select><br />
</div>
</fieldset>
<div class="dialogTop_padd"></div>
<!--- fieldset for box # -->
<fieldset>
<legend>Box Details</legend>
<div class="spacer"></div>
<div>
<label for="BA_box">Box#:</label><br />
<input id="BA_box" name="BA_box" type="text" size="32" maxlength="128" /><br />
</div>
<div>
<label for="BA_destdate">Destroy date:</label>
<input id="BA_destdate" name="BA_destdate" type="text" size="32" maxlength="128" value = "" /><br />
</div>
</fieldset>
<div class="dialogTop_padd"></div>
<!--- fieldset for authorisation -->
<fieldset>
<legend>Authorisation</legend>
<div class="spacer"></div>
<div>
<label for="BA_authorised">Requested By:</label>
<input id="BA_authorised" name="BA_authorised" type="text" value="<?php echo $_SESSION['kt_name_usr']; ?>"><br />
</div>
</fieldset>
<!--- div to show callback result from ajax via dialog -->
<br />
<div id="BA_addbox"></div>
<br />
<input class="AddBoxSubmitButton" type="submit" id="submit" name="submit" value="Add Box" />
<input class="AddBoxResetButton" type="reset" name="cancel" value="Clear Form" />
<!--- buttons to submit form and reset form to default status -->
<!-- <button id="BA_submit" class="submitbutton icon-right ui-state-default2 ui-corner-all"><span class="ui-icon ui-icon-circle-plus"></span>Add Box</button>
<button type="reset" id="BA_reset" class="resetbutton icon-right ui-state-default2 ui-corner-all"><span class="ui-icon ui-icon-circle-plus"></span>Reset</button>
--><br />
</form>
<br />
</div>
jquery code
$(function(){
$("#BA_boxform").submit(function(){
var formdata = $('#BA_boxform').serialize();
alert(formdata);
$.ajax({
type: "POST",
url: "/domain/admin/requests/boxes/boxesadd.php",
data: formdata,
dataType: 'json',
success: function(msg){
//$("#confirm_department").hide();
/*
var $dialog = $('<div id="dialog"></div>')
.html('Your intake was successfully submitted and will be viewable in the reporting area.<br /><br />Thank you.');
$dialog.dialog({
autoOpen: true,
modal: true,
title: 'Box intake submission successfull',
width: 400,
height: 200,
draggable: false,
resizable: false,
buttons: {
Close: function() {
$( this ).dialog( "close" );
}
}
});
*/
//alert('You have succesfully submitted your ' + msg.company + ' report. Thank you.');
//console.log(msg);
$("#BA_addbox").show();
//$("#formImage .col_1 li").show();
$("#BA_boxform").get(0).reset();
//$("#boxaddform").hide();
}
});
return false;
});
});
// End function to submit box intake form
cutdown php code for illustration
if (isset($_POST['submit'])) { }

Answer 1

jQuery won't serialize submit button:
Docs:
Note: Only "successful controls" are serialized to the string. No
submit button value is serialized since the form was not submitted
using a button.
Workaround is to check if $_POST is not empty:
if (!empty($_POST)) {
// Your code here
}
or check if specific input was set. E.g.
if (isset($_POST['BA_customer'])) {
}

Answer 2

Like said, submit buttons aren't serialized. A possible workaround: { not tested but as i understand it, should work }
$('#BA_boxform input:submit').on('click', function () {
var formdata = $('#BA_boxform').serialize() + '&submit=' + $(this).val();
//....
return false;
});