regex to get referring domain

[clicktrack]

I am trying to check the referring domain and match certain domains and got part way there but not all of the way.

Ideally I want to check referrer and if it matches google, yahoo, bing, msn, etc. I want to get which one so I can change some stuff on the site for them.


So far I have something like this.

var url = document.referrer;
patternstring =  /^https?:\/\/(\w+\.)?(google|yahoo|msn)\./;
matcher = url.match(patternstring);

This will match but gives back more than I want. I would only want it to give back google or yahoo or msn.

Any help would be appreciated.

[Philip M]

patternstring =  /^(https?:\/\/)(\w+\.)?(google|yahoo|msn)\./;
matcher = url.match(patternstring);
if (matcher !=null) {  // a match was found
alert (matcher[1]);  // http://
alert (matcher[2]);  // www.
alert (matcher[3]); // google or yahoo or msn
}

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