Javascript

Bonjour a tous , est ce que quelqu'un peux m'aider ?

Voici mon code et je me demande pour quoi il ne fonctionne pas..

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<HTML xmlns="http://www.w3.org/1999/xhtml" lang="fr-fr">
<HEAD>
<SCRIPT LANGUAGE="JavaScript">

<!-- Ce script et d'autres sont sur le code java GRATUIT -->
<!-- LE CODE JAVA - http://www.lecodejava.com -->

<!-- Begin
var expDays = 30;
var exp = new Date();
exp.setTime(exp.getTime() + (expDays*24*60*60*1000));
var ShowCount = 0;
var SwapColour;
function ListToDoItems() {
var NumToDoItems = GetCookie('PT_NumToDoList');
var i;
var ToDoItem;
if (NumToDoItems == null) {
NumToDoItems = 0;
}
ShowCount = 0; SwapColour = 0;
for (i=1; i <= NumToDoItems; i++) {
ToDoItem = GetCookie('PT_ToDoItem'+i);
if (ToDoItem != null) {
PrintItem(ToDoItem, i);
}
}
}
function DeleteItem(Count) {
DeleteCookie('PT_ToDoItem'+Count);
window.location = window.location;
}
function PrintItem (ToDoItem, Count) {
var color = "";
SwapColour = 1 - SwapColour;
if (SwapColour==1) {color = "bgcolor='#c0c0c0'"} ;
ShowCount++;
document.write("<tr " + color + ">");
document.write("<td width=10% align=center valign=top><small><b>"+ShowCount);
document.write("<td width=75% align=left ><small>"+ToDoItem);
document.write("<td width=15% align=center><small>"+"<a href='javascript:DeleteItem(" + Count + ")'>Effacer</a>");
}
function AddItem() {
var NumToDoItems = GetCookie('PT_NumToDoList');
var i;
var ToDoItem;
if (NumToDoItems == null) {
NumToDoItems = 0;
}
ToDoItem = prompt("Ajouter une information");
if ((ToDoItem != null) && (ToDoItem != "undefined" )) {
NumToDoItems++;
SetCookie('PT_ToDoItem'+NumToDoItems, ToDoItem, exp);
SetCookie('PT_NumToDoList',NumToDoItems, exp);
window.location = window.location;
}
}
function set() {
VisitorName = prompt("Qui etes vous?");
SetCookie ('VisitorName', VisitorName, exp);
SetCookie ('WWHCount', 0, exp);
SetCookie ('WWhenH', 0, exp);
}
function getCookieVal (offset) {
var endstr = document.cookie.indexOf (";", offset);
if (endstr == -1)
endstr = document.cookie.length;
return unescape(document.cookie.substring(offset, endstr));
}
function GetCookie (name) {
var arg = name + "=";
var alen = arg.length;
var clen = document.cookie.length;
var i = 0;
while (i < clen) {
var j = i + alen;
if (document.cookie.substring(i, j) == arg)
return getCookieVal (j);
i = document.cookie.indexOf(" ", i) + 1;
if (i == 0) break;
}
return null;
}
function SetCookie (name, value) {
var argv = SetCookie.arguments;
var argc = SetCookie.arguments.length;
var expires = (argc > 2) ? argv[2] : null;
var path = (argc > 3) ? argv[3] : null;
var domain = (argc > 4) ? argv[4] : null;
var secure = (argc > 5) ? argv[5] : false;
document.cookie = name + "=" + escape (value) +
((expires == null) ? "" : ("; expires=" + expires.toGMTString())) +
((path == null) ? "" : ("; path=" + path)) +
((domain == null) ? "" : ("; domain=" + domain)) +
((secure == true) ? "; secure" : "");
}
function DeleteCookie (name) {
var exp = new Date();
exp.setTime (exp.getTime() - 1);
var cval = GetCookie (name);
document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}
// End -->
</script>
</HEAD>
<BODY>

<b><center><big>LA CREATION D'UNE LISTE</big><center></b>
<hr><br>
<table width=100%>
<SCRIPT LANGUAGE="JavaScript">
<!-- Begin
ListToDoItems();
// End -->
</SCRIPT>
</table>
<br><hr>
<center>
<a href="javascript:AddItem()">Ajouter</a>
</center>

</BODY>
</HTML>