How to check if URL exists..?

[Dragonbaki]

Hi guys.,

I have a textbox for entering URL. I validate that URL using regular expression. Now the problem is, How do i know whether the entered URL is exist or not.?

For example, if user enter "http://www.daniweb.cam" rather entering "http://www.daniweb.com", how do i intimate them that the entered url is not valid.?

Is it possible..?

Please kindly advise me....

Thanks,
DragonBaki.

[Airshow]

Dragonbaki,

I've not needed to do this but here are my thoughts .....

The most efficient way would be to make what's called a "HEAD request" and the easiest way I can find to do this is a jQuery plugin:
http://plugins.jquery.com/project/jqHead

As written, I'm pretty certain this plugin won't handle cross-domain requests, which may be an issue for you.

For cross-domain, you have a couple of basic options:Flash-proxy: I like FlXHR . With a little thought, this should be usable with a modified jqHead plugin, because core jquery allows you to specify your own xmlhttp object in a $.ajax request (see this and jquery API).
PHP Proxy: Build you own or find a script on the web. With this approach, javascript will make its request to a same-domain php script (ie on same server as the current web page); the script will use php's capability to make a request to another domain (I'm no expert here - see PHP manual).
Airshow