How to getting values from cookies to set widgets?
function getCookieData(labelName) {
//from Danny Goodman
var labelLen = labelName.length;
// read cookie property only once for speed
var cookieData = document.cookie;
var cLen = cookieData.length;
var i = 0;
var cEnd;
while (i < cLen) {
var j = i + labelLen;
if (cookieData.substring(i,j) == labelName) {
cEnd = cookieData.indexOf(";",j);
if (cEnd == -1) {
cEnd = cookieData.length;
}
return unescape(cookieData.substring(j+1, [...]
How to reload the current page ?
window.location.reload(true);
how to force a page to go to another page using JavaScript ?
How to convert a string to a number using JavaScript?
You can use the parseInt() and parseFloat() methods. Notice that extra letters following a valid number are ignored, which is kinda wierd but convenient at times.
parseInt(”100″) ==> 100
parseFloat(”98.6″) [...]
eval()?
The eval() method is incredibly powerful allowing you to execute snippets of code during execution.
<script type="text/javascript">
var USA_Texas_Austin = "521,289";
document.write("Population is "+eval("USA_"+"Texas_"+"Austin"));
</script>
This produces
Population is 521,289
What does break and continue statements do?
Continue statement continues the current loop (if label not specified) in a new iteration whereas break statement exits the current loop.
How to create a function using [...]
How to Handle Event Handlers?
You can add an event handler in the HTML definition of the element like this,
<script type="text/javascript"><!–
function hitme() {
alert("I’ve been hit!");
}
// –>
</script>
<input type="button" id="hitme" name="hitme" value="hit me" onclick="hitme()"
Or, interestingly enough you can just assign the event’s name on the object directly with a reference to the method you want to assign.
<input type="button" [...]
What does undefined value mean in javascript?
Undefined value means the variable used in the code doesn’t exist or is not assigned any value or the property doesn’t exist.
What is the difference between undefined value and null value?
(i)Undefined value cannot be explicitly stated that is there is no keyword called undefined whereas null value has keyword [...]
To put a “close window” link on a page ?
<a href=’javascript:window.close()’ class=’mainnav’> Close </a>
How to hide javascript code from old browsers that dont run it?
Use the below specified style of comments
<script language=javascript> <!– javascript code goes here // –> or Use the <NOSCRIPT>some html code </NOSCRIPT>
tags and code the display html statements between these [...]
What Web sites do you feel use JavaScript most effectively (i.e., best-in-class examples)? The worst?
The best sites are the ones that use JavaScript so transparently, that I’m not aware that there is any scripting on the page. The worst sites are those that try to impress me with how much scripting is on the page.
How [...]
How to embed javascript in a web page?
javascript code can be embedded in a web page between
<script langugage="javascript"></script>
tags
What and where are the best JavaScript resources on the Web?
The Web has several FAQ areas on JavaScript. The best place to start is something called the meta-FAQ [14-Jan-2001 Editor's Note: I can't point to it [...]
What does isNaN function do?
Return true if the argument is not a number.
What is negative infinity?
It’s a number in JavaScript, derived by dividing negative number by zero.
In a pop-up browser window, how do you refer to the main browser window that opened it?
Use window.opener to refer to the main window from pop-ups.
What is the data [...]
What are synchronized methods and synchronized statements?
Synchronized methods are methods that are used to control access to an object. A thread only executes a synchronized method after it has acquired the lock for the method’s object or class. Synchronized statements are similar to synchronized methods. A synchronized statement can only be executed after a thread [...]
