如何通过导航栏的高度更改平滑滚动JQuery动画的偏移量

Question

All my smooth scrolling works perfectly, however, the anchor stops at the very top of the page, but my navigation bar is fixed to the top, so what I need it to do, is offset the top by the height of the navbar. How would I go about this?

<script>
  $(document).ready(function(){
    // Add smooth scrolling to all links
    $("a").on('click', function(event) {

      // Make sure this.hash has a value before overriding default behavior
      if (this.hash !== "") {
        // Prevent default anchor click behavior
        event.preventDefault();

        // Store hash
        var hash = this.hash;

        // Using jQuery's animate() method to add smooth page scroll
        // The optional number (800) specifies the number of milliseconds
        // it takes to scroll to the specified area
        $('html, body').animate({
          scrollTop: $(hash).offset().top
        }, 1000, function(){

          // Add hash (#) to URL when done scrolling (default click behavior)
          window.location.hash = hash;
        });
      } // End if
    });
  });
</script>

Answer 1

非常简单： scrollTop: $('#hash').offset().top - navbarHeight 。