The situation makes scripting a challenge, especially for newcomers who may not be aware of the limitations of earlier browsers. A lot of effort in my books and ancillary material goes toward helping scripter know what features work in which browsers and how to either workaround limitations in earlier browsers or raise the compatibility common denominator.
Designing scripts for a Web site requires making some hard decisions about if, when, and how to implement the advantages scripting offers a page to your audience. For public Web sites, I recommend using scripting in an additive way: let sufficient content stand on its own, but let scriptable browser users receive an enhanced experience, preferably with the same HTML document.
22 :: What does isNaN function do?Return true if the argument is not a number.
24 :: 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.
26 :: Methods GET and POST in HTML forms - what's the difference?GET: Parameters are passed in the query string. Maximum amount of data that can be sent via the GET method is limited to about 2kb.
POST: Parameters are passed in the request body. There is no limit to the amount of data that can be transferred using POST. However, there are limits on the maximum amount of data that can be transferred in one name/value pair.
1. To remove an item from a list set it to null
mySelectObject.options = null;
2. To truncate a list set its length to the maximum size you desire
mySelectObject.length = 2;
3. To delete all options in a select object set the length to 0.
29 :: What does the "Access is Denied" IE error mean?The "Access Denied" error in any browser is due to the following reason.
document's domain is different from the document containing the script.
computation, so it is always faster than any server-side script like ASP, PHP, etc..