jquery scrollspy插件将允许您轻松做到这一点。 https://github.com/thesmart/jquery-scrollspy

$('.tile').on('scrollSpy:enter', function() {
    console.log('enter:', $(this).attr('id'));
});

$('.tile').on('scrollSpy:exit', function() {
    console.log('exit:', $(this).attr('id'));
});

$('.tile').scrollSpy();

我们可以在使用ES6的现代浏览器中做这样的事情:

const isFullySeen = el => el &&
  typeof el.getBoundingClientRect === 'function' &&
  el.getBoundingClientRect()['bottom'] + window.scrollY <= 
    window.innerHeight + window.scrollY && 
  el.getBoundingClientRect()['top'] + window.scrollY <= 
    window.innerHeight + window.scrollY;

这里有一种使用Mootools实现相同目标的方法，可以是水平的、垂直的或两者都有。

Element.implement({
inVerticalView: function (full) {
    if (typeOf(full) === "null") {
        full = true;
    }

    if (this.getStyle('display') === 'none') {
        return false;
    }

    // Window Size and Scroll
    var windowScroll = window.getScroll();
    var windowSize = window.getSize();
    // Element Size and Scroll
    var elementPosition = this.getPosition();
    var elementSize = this.getSize();

    // Calculation Variables
    var docViewTop = windowScroll.y;
    var docViewBottom = docViewTop + windowSize.y;
    var elemTop = elementPosition.y;
    var elemBottom = elemTop + elementSize.y;

    if (full) {
        return ((elemBottom >= docViewTop) && (elemTop <= docViewBottom)
            && (elemBottom <= docViewBottom) && (elemTop >= docViewTop) );
    } else {
        return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop));
    }
},
inHorizontalView: function(full) {
    if (typeOf(full) === "null") {
        full = true;
    }

    if (this.getStyle('display') === 'none') {
        return false;
    }

    // Window Size and Scroll
    var windowScroll = window.getScroll();
    var windowSize = window.getSize();
    // Element Size and Scroll
    var elementPosition = this.getPosition();
    var elementSize = this.getSize();

    // Calculation Variables
    var docViewLeft = windowScroll.x;
    var docViewRight = docViewLeft + windowSize.x;
    var elemLeft = elementPosition.x;
    var elemRight = elemLeft + elementSize.x;

    if (full) {
        return ((elemRight >= docViewLeft) && (elemLeft <= docViewRight)
            && (elemRight <= docViewRight) && (elemLeft >= docViewLeft) );
    } else {
        return ((elemRight <= docViewRight) && (elemLeft >= docViewLeft));
    }
},
inView: function(full) {
    return this.inHorizontalView(full) && this.inVerticalView(full);
}});

一个基于这个答案的例子，检查一个元素是否有75%可见(即小于25%的元素在屏幕之外)。

function isScrolledIntoView(el) {
  // check for 75% visible
  var percentVisible = 0.75;
  var elemTop = el.getBoundingClientRect().top;
  var elemBottom = el.getBoundingClientRect().bottom;
  var elemHeight = el.getBoundingClientRect().height;
  var overhang = elemHeight * (1 - percentVisible);

  var isVisible = (elemTop >= -overhang) && (elemBottom <= window.innerHeight + overhang);
  return isVisible;
}

这将考虑元素的任何填充、边框或边距，以及大于视口本身的元素。

function inViewport($ele) {
    var lBound = $(window).scrollTop(),
        uBound = lBound + $(window).height(),
        top = $ele.offset().top,
        bottom = top + $ele.outerHeight(true);

    return (top > lBound && top < uBound)
        || (bottom > lBound && bottom < uBound)
        || (lBound >= top && lBound <= bottom)
        || (uBound >= top && uBound <= bottom);
}

要调用它，可以使用这样的代码:

var $myElement = $('#my-element'),
    canUserSeeIt = inViewport($myElement);

console.log(canUserSeeIt); // true, if element is visible; false otherwise

修改了已接受的答案，以便元素必须将其display属性设置为“none”以外的值，以便质量为可见。

function isScrolledIntoView(elem) {
   var docViewTop = $(window).scrollTop();
  var docViewBottom = docViewTop + $(window).height();

  var elemTop = $(elem).offset().top;
  var elemBottom = elemTop + $(elem).height();
  var elemDisplayNotNone = $(elem).css("display") !== "none";

  return ((elemBottom <= docViewBottom) && (elemTop >= docViewTop) && elemDisplayNotNone);
}