html - 使用 HTML/CSS 将鼠标悬停在图像上的放大效果

Question

只用html和css可以达到这个效果吗？在示例图像中，您可以看到鼠标悬停的放大圆形区域(来自更高分辨率的源图片)。它不是圆形区域或有边框。

example of desired Magnifiing effect over a image with mouse hover with HTML/CSS

在此site example你可以看到一个很好的例子(但它使用 jquery，我不知道将这段代码放在我的网页中的什么地方)

这里有人能告诉我如何开始编码吗？ (如果这是可行的)。非常感谢!

Answer 1

使用第二个例子很简单像这样只复制 html 页面中的 html、css 页面中的 css 和 html 页面中的 jquery 代码

<script type="text/javascript">$(document).ready(function(){

var native_width = 0;
var native_height = 0;

//Now the mousemove function
$(".magnify").mousemove(function(e){
    //When the user hovers on the image, the script will first calculate
    //the native dimensions if they don't exist. Only after the native dimensions
    //are available, the script will show the zoomed version.
    if(!native_width && !native_height)
    {
        //This will create a new image object with the same image as that in .small
        //We cannot directly get the dimensions from .small because of the 
        //width specified to 200px in the html. To get the actual dimensions we have
        //created this image object.
        var image_object = new Image();
        image_object.src = $(".small").attr("src");

        //This code is wrapped in the .load function which is important.
        //width and height of the object would return 0 if accessed before 
        //the image gets loaded.
        native_width = image_object.width;
        native_height = image_object.height;
    }
    else
    {
        //x/y coordinates of the mouse
        //This is the position of .magnify with respect to the document.
        var magnify_offset = $(this).offset();
        //We will deduct the positions of .magnify from the mouse positions with
        //respect to the document to get the mouse positions with respect to the 
        //container(.magnify)
        var mx = e.pageX - magnify_offset.left;
        var my = e.pageY - magnify_offset.top;

        //Finally the code to fade out the glass if the mouse is outside the container
        if(mx < $(this).width() && my < $(this).height() && mx > 0 && my > 0)
        {
            $(".large").fadeIn(100);
        }
        else
        {
            $(".large").fadeOut(100);
        }
        if($(".large").is(":visible"))
        {
            //The background position of .large will be changed according to the position
            //of the mouse over the .small image. So we will get the ratio of the pixel
            //under the mouse pointer with respect to the image and use that to position the 
            //large image inside the magnifying glass
            var rx = Math.round(mx/$(".small").width()*native_width - $(".large").width()/2)*-1;
            var ry = Math.round(my/$(".small").height()*native_height - $(".large").height()/2)*-1;
            var bgp = rx + "px " + ry + "px";

            //Time to move the magnifying glass with the mouse
            var px = mx - $(".large").width()/2;
            var py = my - $(".large").height()/2;
            //Now the glass moves with the mouse
            //The logic is to deduct half of the glass's width and height from the 
            //mouse coordinates to place it with its center at the mouse coordinates

            //If you hover on the image now, you should see the magnifying glass in action
            $(".large").css({left: px, top: py, backgroundPosition: bgp});
        }
    }
})

在您的 html 页面之间和之中使用此代码

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