Determine domain name in JavaScript?

What's the difference between using

if (document.domain.toLowerCase(开发者_如何学Python).indexOf("domainName") != -1)

and

if(window.location.href.match(/:\/\/(.[^/]+)/)[1].toLowerCase().indexOf("domainName") != -1)

and

if(window.location.hostname.toLowerCase().indexOf("domainName") != -1)

I'm just trying to match on a certain domainName and want to use the best approach.

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Best and most readable would be:

if(location.hostname == "mysite.com"){

}

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Update:

Or as Patrick pointed out if you are only looking for part of the domain name I would use match.

if(location.hostname.match('mysite')){} // will return null if no match is found

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Readable Method:

You can use endsWith() to compare the end of the hostname string with the domain name:

location.hostname === 'stackexchange.com' || location.hostname.endsWith('.stackexchange.com')

Note: This requires ECMAScript 6 (ES6) support.

Short Method:

Or if you would prefer to use a regex with the test() method, you can use:

/(^|\.)stackexchange\.com$/.test(location.hostname)

Split/Join Array-to-String Method:

Additionally, you can also split() the hostname into an array based on the . character. Then you can take the last two elements (the domain name and extension) using slice(), and join() them back together with the . character as the separator, which will allow you to compare directly to the expected domain name:

location.hostname.split('.').slice(-2).join('.') === 'stackexchange.com'

This will return true for the following types of URLs:

• https://stackexchange.com/
• https://stackexchange.com/tour
• https://dba.stackexchange.com/
• https://dba.stackexchange.com/tour

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All of ur solutions aren't efficient! they will basically match everything that contains the domain name.. e.g. lets say the domain is "domain.com"

• `http://prefixdomain.com`
• `http://domain.com.jo`
• sub-domains `http://sub.domain.com`
• paths: `http://whatever.com/domain.com`

so best solution would be

function isEquals(myhost){
              var hostName = window.location.hostname.split('.');
              myhost = myhost.split(".");
              //handle stuff like site:.com or ..com
              for (var x in myhost)
                if (myhost[x] == "") myhost.splice(x,1);

          //j is where to start comparing in the hostname of the url in question
          var j = hostName.length - myhost.length;
          for(var i in myhost)
          {
              //if j is undefined or doesn't equal the hostname to match return false 
              if (!hostName[j] || hostName[j].toLowerCase() != host[i].toLowerCase())
                  return false;
              j++;
          }
          return true;
      }

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The first and third should be simple and quick. Of the two, I don't think it really matters as long as you're just testing the domain.

If you're testing a sub-domain, then consider that document.domain be modified in javascript, while window.location.hostname can't.

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Well, window.location is the more standard way, so I'd suggest that over document.domain. IndexOf will match substrings, which probably isn't what you want. Why not just:

window.location.hostname == "stackoverflow.com"?

I guess for some sites you may have an optional subdomain. Like www.domain.com and just domain.com both going to the same place. If that's a concern you could make some ugly regex, or you could just split on dots:

var domainParts = window.location.hostname.split(".");
domainParts[domainParts.length - 2] == "stackoverflow"

I don't think case matters, at least in the browsers I tried (Firefox and Chrome) they normalize the domain name to lowercase automatically.