2. Previous Work Review
• http://pirate.shu.edu/~marinom6/work.html
• Please Note only previously due HW assignments are posted on my
pirate.shu.edu web space
• Begin organizing your creating files for this course into an easy to find folder
on your desktop for easy FTP later on
3. Important Notes
• XML works well with JavaScript
• JavaScript can help in getting a cookie in addition to setting a cookie
• A cookie stores small amounts of data
• The expires function is used to set an expiration date on a cookie
• Cookies are available in the same directory the cookie was created in
5. XML and JavaScript [JS file]
function showData()
{
var xml = new XMLHttpRequest();
var addressHTML = "";
var addressbook = document.getElementById("addressbook");
xml.open("GET", "addressdata.xml", false);
xml.send("");
var xmlDoc = xml.responseXML;
var names = xmlDoc.getElementsByTagName("name");
var mails = xmlDoc.getElementsByTagName("email");
for (var i = 0; i < names.length; i++)
{
var name = names[i].childNodes[0].nodeValue;
var mail = mails[i].childNodes[0].nodeValue;
addressHTML += "<li>" + name + "(" + mail + ")</li>n";
}
addressbook.innerHTML = addressHTML;
}
6. Concerns with Cookies
• Cookies can be overwritten in the browser.
• Some browsers allow for this and others can be edit by opening the file which stores
the cookies.
• Cookies are prime targets for sql injection. Imagine you are performing a
select based on the username:
• select student_id from students where username = “<username>” where <username>
is the valued stored in the cookie.
8. Building Assignment 7
function checkCookie()
{
alert(document.cookie);
var username=getCookie("username");
if (username!=null && username!="")
{
alert("Welcome again " + username);
}
else
{
username=prompt("Please enter your name:","");
if (username!=null && username!="")
{
setCookie("username",username,365);
}
}
}
9. External Version [Assignment 7] – HTML File
<!DOCTYPE html>
<html>
<head>
<script src="js/scripts.js"></script>
</head>
<body onload="checkCookie()">Marino's cookie checker</body>
</html>
10. External Version [Assignment 7] – JS File
function checkCookie()
{
alert(document.cookie);
var username=getCookie("username");
if (username!=null && username!="")
{
alert("Welcome again " + username);
}
else
{
username=prompt("Please enter your name:","");
if (username!=null && username!="")
{
setCookie("username",username,365);
}
}
}
11. onclick Display Date and Time
<!DOCTYPE html>
<html>
<body>
<h2>Date and Time</h2>
<button type="button"
onclick="document.getElementById('demo').innerHTML = Date()">
Click me to display Date and Time.</button>
<p id="demo"></p>
</body>
</html>
12. JavaScript Compared to HTML/CSS
• HTML to define the content of web pages
• CSS to specify the layout of web pages
• JavaScript to program the behavior of web pages
13. More onclick Examples
<!DOCTYPE html>
<html>
<body>
<button onclick="document.getElementById('demo').innerHTML=Date()">The time
is?</button>
<p id="demo"></p>
</body>
</html>
15. Common JS/HTML Elements
Event Description
onchange An HTML element has been changed
onclick The user clicks an HTML element
onmouseover The user moves the mouse over an HTML
element
onmouseout The user moves the mouse away from an
HTML element
onkeydown The user pushes a keyboard key
onload The browser has finished loading the page
16. JavaScript - Java
• Arrays
• Booleans
• Math Class
• Random Class
• Objects
• Functions
• Assignment requirements
