如何在php变量中存储javascript函数值

Question

function check_val(val) {
   document.getElementById("select_action")=val; 
   alert(val);
   return val;
}

this is my javascript function

<select name='select'  id='select'   onchange='check_val(this.value)'> 
<option value='0'><------select------></option>
<option value='4'>apple</option>
<option value='5'>mango</option>
<option value='6'>berry</option>
</select>
<?php <input type=hidden name='select' value=???> //by using javascript I need the value

this is my select tag now I want to put the values inside a hidden field

Answer 1

Pam, you don't need php at all for this, just set the value of the hidden input in your javascript function with the manipulated val

function check_val(val) {
    val++;  // do things to val (add 1) 
    document.getElementById("hidden_input").value=val; //set value in the hidden input
    return;
}

Make sure your hidden input has an ID

<select name="select" id="select" onchange="check_val(this.value)"> 
    <option value='0'><------select------></option>
    <option value='4'>apple</option>
    <option value='5'>mango</option>
    <option value='6'>berry</option>
</select>

<input id="hidden_input" type="hidden" name="hidden_input" value="0">

On the page that you are posting to, you will access the data in PHP with

echo $_POST['hidden_input'];
// or
echo $_REQUEST['hidden_input'];