【发布时间】：2020-02-22 20:19:59
【问题描述】：
// magnify hover
function magnify(imgID, zoom) {
var img, glass, w, h, bw;
img = document.getElementById(imgID);
/*create magnifier glass:*/
glass = document.createElement("DIV");
glass.setAttribute("class", "img-magnifier-glass");
/*insert magnifier glass:*/
img.parentElement.insertBefore(glass, img);
/*set background properties for the magnifier glass:*/
glass.style.backgroundImage = "url('" + img.src + "')";
glass.style.backgroundRepeat = "no-repeat";
glass.style.backgroundSize = (img.width * zoom) + "px " + (img.height * zoom) + "px";
bw = 3;
w = glass.offsetWidth / 2;
h = glass.offsetHeight / 2;
/*execute a function when someone moves the magnifier glass over the image:*/
glass.addEventListener("mousemove", moveMagnifier);
img.addEventListener("mousemove", moveMagnifier);
/*and also for touch screens:*/
glass.addEventListener("touchmove", moveMagnifier);
img.addEventListener("touchmove", moveMagnifier);
function moveMagnifier(e) {
var pos, x, y;
/*prevent any other actions that may occur when moving over the image*/
e.preventDefault();
/*get the cursor's x and y positions:*/
pos = getCursorPos(e);
x = pos.x;
y = pos.y;
/*prevent the magnifier glass from being positioned outside the image:*/
if (x > img.width - (w / zoom)) {x = img.width - (w / zoom);}
if (x < w / zoom) {x = w / zoom;}
if (y > img.height - (h / zoom)) {y = img.height - (h / zoom);}
if (y < h / zoom) {y = h / zoom;}
/*set the position of the magnifier glass:*/
glass.style.left = (x - w) + "px";
glass.style.top = (y - h) + "px";
/*display what the magnifier glass "sees":*/
glass.style.backgroundPosition = "-" + ((x * zoom) - w + bw) + "px -" + ((y * zoom) - h + bw) + "px";
}
function getCursorPos(e) {
var a, x = 0, y = 0;
e = e || window.event;
/*get the x and y positions of the image:*/
a = img.getBoundingClientRect();
/*calculate the cursor's x and y coordinates, relative to the image:*/
x = e.pageX - a.left;
y = e.pageY - a.top;
/*consider any page scrolling:*/
x = x - window.pageXOffset;
y = y - window.pageYOffset;
return {x : x, y : y};
}
}
/* Initiate Magnify Function
with the id of the image, and the strength of the magnifier glass:*/
magnify("mag", 2);.img-magnifier-glass {
position: absolute;
z-index: 3;
border: 3px solid #000;
border-radius: 40%;
cursor: none;
/*Set the size of the magnifier glass:*/
width: 100px;
height: 100px;
}<table class="img-magnifier-container" width="115" border="0" cellpadding="0" cellspacing="0" style="display: inline-block"><tr><td width="115" style="text-align: center"><center><a href="https://www.imdb.com/title/tt3315342/" title="Logan 4K (2017)" target="_blank"><img class="cover" width="115" height="133" border="0" id="mag" class="pstrart" id="pstr" src="https://images.static-bluray.com/movies/covers/174423_front.jpg" style=""></a></center><center><input type="checkbox" name="movieboxes" value="Logan" style="width: 15px; height: 15px; margin: 0px;">你好，
如何使放大镜仅在我将鼠标悬停在图像上时显示？我已尝试在此网站和其他地方进行搜索，但我的理解不足以使解决方案适用于我的情况。
我从 W3School 复制了这个，但他们没有说明我可以让它在我将鼠标悬停在它上面时显示的部分。
我看到了模态框，并试图复制它的悬停功能，但它似乎不起作用。 谢谢！
【问题讨论】：
标签： javascript html css hover