Solved

Check Domain Name Syntax with JS

Posted on 2007-03-18
1
196 Views
Last Modified: 2008-03-31
Hello,

I would like to use JavaScript to determine the syntax validity of a domain name. This will be used in an internal Intranet, so in addition to all standard domain name extensions, other internal extensions should be allowed as well.

1. There should be at least 1 dot.
2. Only letters, numbers and dashes should be allowed before the LAST dot.
3. Only letters should be allowed AFTER the LAST dot.
4. This should be case insensitive

All of these should PASS
        www.example.com
        www.example.intranet
        sub.portal.example.intranet
        example-web-page-123.mobi
        2534457.2343.com
        234-64.23.112.intrra
        234-64.23.112.2323.5234.34323.43234.234.net


But all of these should FAIL:
        example  com
        example@example.com
        sub_portal.example.intranet
        example-web-page-123
        192.168.0.1





This does NOT work.  Any ideas how to fix it?
Thanks!

<!doctype html public "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<script>
function isValidDomain(obj){
    var urlPattern = /^(?:(?:[-a-z0-9]*[a-z0-9])?\.)+([a-z])?/;
      return urlPattern.test(obj.value);      
      }

</script>
</head>
<body>
<form name="frm1" method="post" action="" onsubmit="return ">
<input type="text" name="txt1" value="webaddress.com">
<input type="button" value="Valid Domain?" onclick="alert(isValidDomain(this.form.txt1))">
</form>
</body>
</html>
0
Comment
Question by:hankknight
1 Comment
 
LVL 15

Accepted Solution

by:
stanscott2 earned 500 total points
ID: 18743956
Use this regular expression:

/^[A-Za-z0-9\-\.]*\.[A-Za-z]*$/
0

Featured Post

Free Tool: IP Lookup

Get more info about an IP address or domain name, such as organization, abuse contacts and geolocation.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Avoid defining the variables in the global scope; trying to define them in a local function scope. Because:   • Look-up is performed every time a variable is accessed.   • Variables are resolved backwards from most specific to least specific scope…
Nothing in an HTTP request can be trusted, including HTTP headers and form data.  A form token is a tool that can be used to guard against request forgeries (CSRF).  This article shows an improved approach to form tokens, making it more difficult to…
The viewer will learn the basics of jQuery, including how to invoke it on a web page. Reference your jQuery libraries: (CODE) Include your new external js/jQuery file: (CODE) Write your first lines of code to setup your site for jQuery.: (CODE)
The viewer will learn the basics of jQuery including how to code hide show and toggles. Reference your jQuery libraries: (CODE) Include your new external js/jQuery file: (CODE) Write your first lines of code to setup your site for jQuery…

820 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question