隐藏输入值到PHP会话

Question

I have a form, which uses the following input towards the end:

<input type="hidden" id="ct_count" name="ct_count" value=""/>

The initialisation of the form is:

<form action="email_submission.php" method="post" id="form1" onsubmit="mySubmit();">

And the mySubmit function is:

function mySubmit() {
  document.getElementById('ct_count').value = ct;
  document.getElementById("form1").submit();
}

When i hit submit, I want to pass the value of ct, which is a variable count on the page, to email_submission.php and store it in a session variable. The session variable is returning blank on every submit, and i'm unsure if the value of the "ct" variable used is being passed through on the hidden field.

Is someone able to pick up where i'm going wrong? There are already variables stored correctly through this, so it's not my session settings as far as i know.

tldr: What's the correct way to take a javascript variable count and pass it through form submit to php?

EDIT: this is the code for adding fields. intiial loop for the variable "ct"

function new_link()
{
ct++;
<?php $ct = $ct + 1; ?>

document.getElementById("sec4_lender").setAttribute('name', 'sec4_lender_<?php echo $ct;?>');
document.getElementById("sec4_balance").setAttribute('name', 'sec4_balance_<?php echo $ct;?>');
document.getElementById("sec4_termdate").setAttribute('name', 'sec4_lender_<?php echo $ct;?>');
document.getElementById("sec4_security").setAttribute('name', 'sec4_security_<?php echo $ct;?>');
document.getElementById("sec4_description").setAttribute('name', 'sec4_description_<?php echo $ct;?>');
document.getElementById("sec4_status").setAttribute('name', 'sec4_status_<?php echo $ct;?>');
document.getElementById("sec4_repayment").setAttribute('name', 'sec4_repayment_<?php echo $ct;?>');
document.getElementById("sec4_repayment2").setAttribute('name', 'sec4_repayment_2_<?php echo $ct;?>');

var div1 = document.createElement('tr');
div1.id = 'sect4busloan_div_'+ct+'';
// link to delete extended form elements
var delLink = '<tr style="text-align:right;margin-right:65px"><a href="javascript:delIt('+ ct +')">Del</a></tr>';
div1.innerHTML = document.getElementById('newlinktpl').innerHTML + delLink;
document.getElementById('newlink').appendChild(div1);

}

// function to delete the newly added set of elements
function delIt(eleId)
{
d = document;
var ele = d.getElementById(eleId);
var parentEle = d.getElementById('newlink');
parentEle.removeChild(parentEle.childNodes[eleId]);
var newct = ct - 1;
ct = newct;
<?php $ct = $ct - 1;?>

}

Answer 1

You're taking the input's value and always setting it to ct -

document.getElementById('ct_count').value = ct;

You should get a warning or error about ct in the console if you do it this. What you should do is set a variable to the value of the input -

var ct = document.getElementById('ct_count').value; 

It also appears that you never set the value of the hidden field, so in the example I post here ct 's value will always be blank.

Answer 2

It turned out that while bug testing i had moved that single session out of the conditionals for my script. So for every page other than the first i was moving on to, it was requesting a blank variable.

Idiocy at its finest. Thank you very much for everyone helping in this matter.