Though a novice in javascript, I need to take javascript variable (an array) reflecting what a user has done on client side and post it to a PHP server page on submit.
It was suggested that I include this as a value in a hidden field in a form to post to the php page. However, since the JS variable is dynamically created by the user, I can't write to the page for inclusion in the form unless I call a function that refreshes the page. To avoid a double page refresh, I'd prefer to have the submit function both grab the data and simultaneously post it to the php script. AJAX if I understand correctly, should not be needed because I'm okay reloading the page once on submit. I just don't want to reload twice.
The following uses the function suggested by Andrew to set the js variable and post. Th form posts as I get the other hidden variable in the form but I am not getting the variable set by js, possibly because there is a mistake with the naming of the variables.
<html>
<head>
<style type="text/css">
select
{
width:100px;
}
</style>
<script type="text/Javascript">
function moveToRightOrLeft(side)
{
if (side == 1)
{
var list1 = document.getElementById('selectLeft');
var list2 = document.getElementById('selectRight');
}
else
{
var list1 = document.getElementById('selectRight');
var list2 = document.getElementById('selectLeft');
}
if (list1.options.length == 0)
{
alert('The list is empty');
return false;
}
else
{
var selectedItem = list1.options[list1.selectedIndex];
move(list2, selectedItem.value, selectedItem.text);
list1.remove(list1.selectedIndex);
if (list1.options.length > 0)
list1.options[0].selected = true;
}
return true;
}
function move(listBoxTo, optionValue, optionDisplayText)
{
var newOption = document.createElement("option");
newOption.value = optionValue;
newOption.text = optionDisplayText;
listBoxTo.add(newOption, null);
return true;
}
function postData(listBoxID)
{
var options = document.getElementById(listBoxID).options;
for (var i = 0; i < options.length; i++)
window.location = "posttoserver.php?data="+options[i].value;
}
function setTheValue(val) {
var options = document.getElementById(listBoxID).options;
var form = document.forms['myForm'];
hiddenField = oFormObject.elements["data"];
hiddenField.value = "val";
}
</script>
</head>
<body>
<select id="selectLeft" multiple="multiple">
<option value="1">Value 1</option>
<option value="2">Value 2</option>
<option value="3">Value 3</option>
</select>
<button onclick="moveToRightOrLeft(2)"><</button>
<button onclick="moveToRightOrLeft(1)">></button>
<select id="selectRight" multiple="multiple">
</select>
<form id="myForm" action="getdata.php" method="get">
<input type="hidden" name="data" />
<input type="hidden" name="mode" value="savedit">
<button onclick="setTheValue(options)">Submit Data</button>
</form>
</body>
</html>
On the other end I have in getdata.php:
<?php
$mode = $_REQUEST['mode'];
$option = $_REQUEST['data'];
echo $mode;
echo $option;
print_r ($option);;
?>