如何向php发送隐藏的输入值

My html code is bellow

<li > <span class="add-on">ADdfgsdfgd</span>

    <input class="" type="text" value="" >
    <input class="picker" type="hidden" name="BIOLOGY" value="">
    <input class="datepicker" type="date">
</li>
<li> <span class="add-on">Ecconomics</span>

    <input class="Ecconomics" type="text" value="">
    <input class="picker" type="hidden" name="ECONOMICS" value="">
    <input class="datepicker" type="date">
</li>
<li> <span class="add-on">Business Study</span>

    <input class="Business Study" type="text" value="">
    <input class="picker" type="hidden" name="BUSINESS STUDIES" value="">
    <input class="datepicker" type="date">
</li>
         <input id="sss" value="get" class="datepicker" type="button">

And jquery code is bellow

$("#sss").on('click', function() {
$('li').each(function(){
  var self= $(this);
  var getDate= self.find('.datepicker').val();
  var getMark= self.find('span + input').val();
  var plusVal = getDate + getMark;

  self.find('.picker').val(plusVal);

});
    });

DEMO

I was able to put each first and last inputs values to middle hidden inputs via jquery.so now i want to send hidden value to php.What is the way of it?

<form action="yourpage.php" method="post">
  <input type="text" value="" name="textbox">
  <input type="hidden" value="<?php echo $some_variable ?>" name="hiddenfield">
</form>

With a form method="post", php creates an array under a variable called $_POST, so all you need to do is collect that and you're good to go.

In my example, you could:

<?php echo $_POST['hiddenfield'] ?>

To pull the variable after a postback.

Do this:

• Assign name to each input.

• In jquery get the value by $("input[name='field_name']").val()

With Jquery I use:

    $.post("profile.php", {sel:"crop",pid:$("#sel_utypes").val()}, function(j)
    {
        //load form
        $("#ext_page").html(j);

        //diplay            
        $("#externalpage").overlay().load();
    });

You can also serialize the forms with $("#fromid").serialize() and send that instead of manually writing the {sel:....}