cis 375—web app dev ii javascript iii. 2 the string object a js string is an object with...
TRANSCRIPT
CIS 375—Web App Dev II
JavaScript III
2
The String Object A JS String is an object with properties
and _________. For more info on JavaScript click here.
http://www.pageresource.com/ http://hotwired.lycos.com/webmonkey/javascript/tutorials/tuto
rial1.html
http://wdvl.internet.com/Authoring/JavaScript/Tutorial/ Examples:var phrase = "W3Schools is great!“ // creates a String
document.write(phrase.length) // displays “19”
var pos = phrase.indexOf("School") // stores “2”
document.write(phrase.substr(2,6)) // displays “School”
3
The Array Object Examplevar famName = new Array(6) // array w/ 6 items
famName[0] = "Jan Egil"
famName[1] = "Tove"
famName[2] = "Hege"
famName[3] = "Stale"
famName[4] = "Kai Jim"
famName[5] = "Borge"
for (i=0; i<6; i++){
document.write(famName[i] + "<br>")
}
4
The Date Object Examplevar today = new Date() // create a date object
var weekday = new Array ("Sunday","Monday","Tuesday","Wednesday","Thursday", "Friday","Saturday") // create an array
var monthname = new Array ("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug", "Sep","Oct","Nov","Dec") // create an array
// display day of week
document.write(weekday[today.getDay()] + “<br>")
// display date
document.write(today.getDate() + ". ")
// display month and full year
document.write(monthname[today.getMonth()] + " ")
document.write(today.getFullYear())
5
The Math Object Example:// get a random number between 0 and 10
randomNum = Math.random()*10
/*
round it up to an integer
so that the result is a random integer from 1
to 10
*/
document.write(Math.ceil(randomNum))
6
The Window Object I Example of a prompt box:
var name = prompt("Please enter your name","")
if (name != null && name != ""){
document.write("Hello " + name)
}
Load a page in the current location:window.location="http://www.w3schools.com/“
Print a page:window.print()
Detect a client’s browser:document.write("You are browsing this site with: "+ navigator.appName)
7
The Window Object II Opening two windows on a button click:<html><head><script language=javascript>function openwindow(){
window.open("http://www.microsoft.com/")window.open("http://www.w3schools.com/")
}</script></head><body><form><input type = button value = "Open Window" onclick =
"openwindow()"></form></body></html>
8
The Frame Object Breaking out of a frame:<html><head><script type="text/javascript">function breakout(){
if (window.top != window.self) { window.top.location="tryjs_breakout.htm" }}</script></head><body><form>To break out of the frame:<input type="button" onclick="breakout()" value="Click me"></form></body></html>
9
The Form Object I Validating a form entry:
<html><head><script type = "text/javascript">function validate(){
x=document.myFormat=x.myEmail.value.indexOf("@")if (at == -1){
alert("Not a valid e-mail")
return false}
}</script></head>
<body>
<form name="myForm"action="tryjs_submitpa
ge.htm"onsubmit="return
validate()">
Enter your E-mail address:
<input type="text" name="myEmail">
<input type="submit" value="Send input">
</form>
</body></html>
10
The Form Object II Setting Focus<html><head><script type = "text/javascript">
function setfocus(){
document.forms[0].field.focus()
}</script></head>
<body><form><input type="text" name="field" size="30">
<input type="button" value="Get Focus" onclick="setfocus()">
</form></body></html>
11
The Form Object III Displaying
form field selections
<html><head><script type =
"text/javascript">function
check(browser){
document.forms[0].answer.value = browser
}</script>
</head>
<body><form>Which browser is your favorite<br><input type = "radio"
name = "browser" onclick = "check(this.value)"value = "Explorer"> MS Internet Explorer <br>
<input type = "radio“ name = "browser" onclick = "check(this.value)"
value = "Netscape"> Netscape Navigator <br>
<input type = "text" name = "answer">
</form>
</body></html>
12
The Browser Object Detecting the client’s browser<html><body><script type="text/javascript">
document.write("BROWSER: ")document.write(navigator.appName + "<br>")document.write("BROWSERVERSION: ")document.write(navigator.appVersion + "<br>")document.write("CODE: ")document.write(navigator.appCodeName + "<br>")document.write("PLATFORM: ")document.write(navigator.platform + "<br>")document.write("REFERRER: ")document.write(document.referrer + "<br>")
</script></body></html>