javascript - 将鼠标悬停在图像上时以受控方式滚动 div 内容

Question

我有一个高度和宽度有限的 div，其中的内容超过了 div 的大小。所以我在 div 的顶部和底部放置了两个图像，我希望内容相对于我悬停的图像上下滚动。我已经设法获得悬停但它不受控制，即使我将鼠标从图像上移开它也会一直持续到最后。因此，我希望一旦我将鼠标移开就停止滚动，当我再次将鼠标悬停在图像上时，我希望滚动从它停止的地方恢复。 jsfiddle

HTML:

<div id="hover"> HOVER ME </div>

<div id="container">

The Mauritius Blue Pigeon is an extinct species of blue pigeon formerly endemic to the Mascarene island of Mauritius in the Indian Ocean east of Madagascar. It has two extinct relatives from the Mascarenes and three extant ones from other islands. It had white hackles around the head, neck and breast and blue plumage on the body, and it was red on the tail and the bare parts of the head. These colours were thought similar to those of the Dutch flag, a resemblance reflected in some of the bird's names. It was 30 cm (12 in) long and larger and more robust than any other blue pigeon species. It could raise its hackles into a ruff, which it used for display. Its call sounded like "barf barf" and it also made a cooing noise. It fed on fruits, nuts, and molluscs, and was once widespread in the forests of Mauritius. The bird was first mentioned in the 17th century and was described several times thereafter, but very few accounts describe the behaviour of living specimens. Several stuffed and at least one live specimen reached Europe in the 1700s and 1800s. Only three stuffed specimens exist today, and only one bird was ever depicted when alive. The species is thought to have become extinct in the 1830s due to deforestation and predation. (Full article...)
Recently featured: Action of 1 January 1800 – Terang Boelan – Muckaty Station............................................................................................................................................................................

The Mauritius Blue Pigeon is an extinct species of blue pigeon formerly endemic to the Mascarene island of Mauritius in the Indian Ocean east of Madagascar. It has two extinct relatives from the Mascarenes and three extant ones from other islands. It had white hackles around the head, neck and breast and blue plumage on the body, and it was red on the tail and the bare parts of the head. These colours were thought similar to those of the Dutch flag, a resemblance reflected in some of the bird's names. It was 30 cm (12 in) long and larger and more robust than any other blue pigeon species. It could raise its hackles into a ruff, which it used for display. Its call sounded like "barf barf" and it also made a cooing noise. It fed on fruits, nuts, and molluscs, and was once widespread in the forests of Mauritius. The bird was first mentioned in the 17th century and was described several times thereafter, but very few accounts describe the behaviour of living specimens. Several stuffed and at least one live specimen reached Europe in the 1700s and 1800s. Only three stuffed specimens exist today, and only one bird was ever depicted when alive. The species is thought to have become extinct in the 1830s due to deforestation and predation. (Full article...)
Recently featured: Action of 1 January 1800 – Terang Boelan – Muckaty Station............................................................................................................................................................................
</div>
<div id="hover2"> HOVER ME </div>​

CSS:

#hover{
   width:200px;
   height:20px;
 border:1px solid #cc0000;   
}
#hover2{
   width:200px;
   height:20px;
 border:1px solid #cc0000;   
}
#container{
  width:500px;
  height:300px;
 overflow-y:auto;   
    border:1px solid #000;
    overflow: hidden;
}
#container div{
  width:100px;
height:100px;    
    float:left;
}​

JavaScript:

$('#hover').hover(function(){
    $('#container').animate({ scrollTop: $('#container')[0].scrollHeight }, 1000);
});
$('#hover2').hover(function(){
    $('#container').animate({ scrollTop: 0 }, 1000);
});     

Answer 1

您需要一次制作一点动画..

var amount = '';

function scroll() {
  $('#container').animate({
    scrollTop: amount
  }, 100, 'linear', function() {
    if (amount != '') {
      scroll();
    }
  });
}
$('#hover').hover(function() {
  amount = '+=10';
  scroll();
}, function() {
  amount = '';
});
$('#hover2').hover(function() {
  amount = '-=10';
  scroll();
}, function() {
  amount = '';
});

#hover {
  width: 200px;
  height: 20px;
  border: 1px solid #cc0000;
}

#hover2 {
  width: 200px;
  height: 20px;
  border: 1px solid #cc0000;
}

#container {
  width: 500px;
  height: 300px;
  overflow-y: auto;
  border: 1px solid #000;
  overflow: hidden;
}

#container div {
  width: 100px;
  height: 100px;
  float: left;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<div id="hover"> HOVER ME </div>

<div id="container">

  The Mauritius Blue Pigeon is an extinct species of blue pigeon formerly endemic to the Mascarene island of Mauritius in the Indian Ocean east of Madagascar. It has two extinct relatives from the Mascarenes and three extant ones from other islands. It
  had white hackles around the head, neck and breast and blue plumage on the body, and it was red on the tail and the bare parts of the head. These colours were thought similar to those of the Dutch flag, a resemblance reflected in some of the bird's
  names. It was 30 cm (12 in) long and larger and more robust than any other blue pigeon species. It could raise its hackles into a ruff, which it used for display. Its call sounded like "barf barf" and it also made a cooing noise. It fed on fruits, nuts,
  and molluscs, and was once widespread in the forests of Mauritius. The bird was first mentioned in the 17th century and was described several times thereafter, but very few accounts describe the behaviour of living specimens. Several stuffed and at
  least one live specimen reached Europe in the 1700s and 1800s. Only three stuffed specimens exist today, and only one bird was ever depicted when alive. The species is thought to have become extinct in the 1830s due to deforestation and predation. (Full
  article...) Recently featured: Action of 1 January 1800 – Terang Boelan – Muckaty Station............................................................................................................................................................................
  The Mauritius Blue Pigeon is an extinct species of blue pigeon formerly endemic to the Mascarene island of Mauritius in the Indian Ocean east of Madagascar. It has two extinct relatives from the Mascarenes and three extant ones from other islands. It
  had white hackles around the head, neck and breast and blue plumage on the body, and it was red on the tail and the bare parts of the head. These colours were thought similar to those of the Dutch flag, a resemblance reflected in some of the bird's
  names. It was 30 cm (12 in) long and larger and more robust than any other blue pigeon species. It could raise its hackles into a ruff, which it used for display. Its call sounded like "barf barf" and it also made a cooing noise. It fed on fruits, nuts,
  and molluscs, and was once widespread in the forests of Mauritius. The bird was first mentioned in the 17th century and was described several times thereafter, but very few accounts describe the behaviour of living specimens. Several stuffed and at
  least one live specimen reached Europe in the 1700s and 1800s. Only three stuffed specimens exist today, and only one bird was ever depicted when alive. The species is thought to have become extinct in the 1830s due to deforestation and predation. (Full
  article...) Recently featured: Action of 1 January 1800 – Terang Boelan – Muckaty Station............................................................................................................................................................................
</div>
<div id="hover2"> HOVER ME </div>

演示 http://jsfiddle.net/gaby/xmAvh/