Download
1 / 12
120 likes | 134 Vues
CIS 375—Web App Dev II. JavaScript III. 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/tutorial1.html
E N D
CIS 375—Web App Dev II JavaScript III
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/tutorial1.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”
The Array Object • Example var 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>") }
The Date Object • Example var 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())
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))
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)
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>
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>
Validating a form entry: <html> <head> <script type = "text/javascript"> function validate(){ x=document.myForm at=x.myEmail.value.indexOf("@") if (at == -1){ alert("Not a valid e-mail") return false } } </script> </head> <body> <form name="myForm" action="tryjs_submitpage.htm" onsubmit="return validate()"> Enter your E-mail address: <input type="text" name="myEmail"> <input type="submit" value="Send input"> </form> </body> </html> The Form Object I
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> The Form Object II
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> The Form Object III
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>
