Getbaseurl() Javascript Call Function In A Href=""

I am calling the based url through javascript in a html page and I want to add the base url to call a link eg. Page The

Solution 1:

function getBaseURL () {
   return location.protocol + "//" + location.hostname + 
      (location.port && ":" + location.port) + "/";
}

Edit: Addressed Mike Samuel's point on nonstandard ports.

Solution 2:

A general solution to allow for the use of <base> (or not) - a further improvement would be to have the baseDocument removed from the baseURL using some kind of regex.

functiongetBaseURL () {
    var baseURL = "";
    var baseDocument = "index.html";

    if (document.getElementsByTagName('base').length > 0) {
        baseURL = document.getElementsByTagName('base')[0].href.replace(baseDocument, "");
    } else {
        baseURL = location.protocol + "//" + location.hostname + (location.port && ":" + location.port) + "/";
    }

    return baseURL;
}

Solution 3:

I am dealing with the same issue, and it isn't so much getting the base URL (as these answers have shown), but calling that javascript function from the element and then adding a relative path. Using @Christian Sanchez answer and other info I've found, this is an option using the onclick of the element:

JAVASCRIPT:

<scripttype="text/javascript">functiongetBaseURL(loc) {
        return location.protocol + "//" + location.hostname +
           (location.port && ":" + location.port) + "/" + loc;
    }
</script>

HTML:

<ahref="filepath/index.html"onclick="getBaseURL(this.href);">TEST LINK</a>

Fiddle is here: http://jsfiddle.net/62g2bkyh/ (hover over link to see URL in fiddle - which shows base URL of iframe).