next js link

                                    <Link href="/shop/[pid]" as={`/shop/${id}`}>
	<a>Shop by menu</a>
</Link>

                                    function getFullUrl(req, fallback) {
  //server side request object(req)
  if(req) {
    return req.protocol + '://' + req.get('host') + req.originalUrl
    
  } //making sure we are on the client side
  else if(!(typeof window === 'undefined')) {
    return window.location.href
    
  } else {
    return fallback
  }
}

//usage on nextjs
static async getInitialProps({req}) {
   let fullUrl = getFullUrl(req, "")//gets the full url or fallback to ""
    return { fullUrl: fullUrl }
}

                                    import Link from 'next/link'

function Home() {
  return (
    <ul>
      <li>
        <Link href="/">
          <a>Home</a>
        </Link>
      </li>
      <li>
        <Link href="/about">
          <a>About Us</a>
        </Link>
      </li>
      <li>
        <Link href="/blog/hello-world">
          <a>Blog Post</a>
        </Link>
      </li>
    </ul>
  )
}

export default Home

                                    import { useRouter } from 'next/router'

function ActiveLink({ children, href }) {
  const router = useRouter()

  const handleClick = (e) => {
    e.preventDefault()
    router.push(href)
  }

  return (
    <a href={href} onClick={handleClick} style={style}>
      {children}
    </a>
  )
}

export default ActiveLink