Regular Expressions in Javascript

[iaresean]

How would I use regular expressions in Javascript?

I have the following function:
function generateUser(){
var temp = window.document.domain_form.domainname.value;
var first = temp.split("."
window.document.domain_form.login.value += first[0];
}

And I have the following code at the end of the domainname input box:
onChange="generateUser()";

Here is my problem:
I have one field called domainname, and another called login.
The user must enter a value for domainame and from this value I want to derive the login. Here are some examples of possible domain names:
mytest.com
second_test.de
stilltesting2.com

I only want the first eight characters, I don't want the .com or .de or .whatever and I don't want the http:// or the www. if they decide to write that out. If it starts with numbers (e.g. 46twenty.com) I would like to drop the numbers, and if it is only numbers (e.g. 46664.com) then I want to keep the login blank.

I have these two regular expressions that might work, but I don't know how to use them. I'm not exactly a reg expr wizz so I won't be surprised if the don't work.

Here they are:
/^(\w{,8})\.\w+$/

/^\d+(\w{,8})\.\w+$/

Please help me to get this working, any and all help is GREATLY appreciated. Thank you.

 

[jemminger]

how about something like this?

<script type=&quot;text/javascript&quot;>
	function getFirstEight(s) {
		var matches = s.replace(&quot;.com&quot;, &quot;&quot;).match(/[a-z]+)+/gi);
		if (matches) return matches.join(&quot;&quot;).substring(0,8);
		else return &quot;&quot;;
	}
</script>

<input type=&quot;text&quot; onchange=&quot;alert(getFirstEight(this.value));&quot; />

=========================================================
-jeff

http://www.jeffemminger.com

try { succeed(); } catch(E) { tryAgain(); }

 

[tanderso]

http://www.google.com/search?q=javascript+regular+expressions

Sincerely,

Tom Anderson
Order amid Chaos, Inc.

http://www.oac-design.com

 

[iaresean]

Well I tried this, but it didn't work, any ideas why?

function generateUser() {
var temp = window.document.domain_form.domainname.value;
var user = temp.replace(/http:\/\//gi,""
user = user.replace(/

http://www./gi,"");

user = user.replace(/^\d+/gi,""
user = user.replace(/..+/gi,""
var first = temp.split("."
window.document.domain_form.login.value += user;
}

First replace is to remove the httpd://
Second replace is to remove the www.
Third replace is to remove any decimals
Fourth replace is to remove .com or .co.uk or .de etc

But it isn't working. I tried this in perl and it works ok, but I need it to work in javascript.

Any help is greatly appreciated.

 

[tanderso]

A period or dot (.) is a wildcard. It means "anything at all". So, if you replace .+ with blank, then nothing remains in your string. It doesn't work in Perl either. You need to escape your dots (eg: \.).

Sincerely,

Tom Anderson
Order amid Chaos, Inc.

http://www.oac-design.com