Get The Current Domain Name With Javascript (Not the path, etc.)

Question

I plan on buying two domain names for the same site. Depending on which domain is used I plan on providing slightly different data on the page. Is there a way for me to de

Answer 1

Combining a few answers from the above, the following works really well for me for destroying Cookies:

  /**
   * Utility method to obtain the domain URI:
   */
  fetchDomainURI() {
    if (window.location.port.length > 0) {
      return window.location.hostname;
    }
    return `.${window.location.hostname.match(/\w*\.\w*$/gi)[0]}`;
  }

Works for IP addresses with ports, e.g., 0.0.0.0:8000 etc, as well as complex domains like app.staging.example.com returning .example.com => allows for cross-domain Cookie setting and destroying.