how to get host name on js code example

Example: js get hostname from url

url = "http://www.example.com/path/to/somwhere";
urlParts = /^(?:\w+\:\/\/)?([^\/]+)([^\?]*)\??(.*)$/.exec(url);
hostname = urlParts[1]; // www.example.com
path = urlParts[2]; // /path/to/somwhere