w3.css
이미지 줌
이미지 확대/축소를 만드는 방법을 알아보자.
이미지 줌 생성
1단계) HTML 추가
<div class="img-zoom-container"> <img id="myimage" src="img_girl.jpg" width="300" height="240" alt="Girl"> <div id="myresult" class="img-zoom-result"></div> </div>
2단계) CSS 추가
컨테이너에는 “상대적” 위치가 있어야 한다.
* {box-sizing: border-box;} .img-zoom-container { position: relative; } .img-zoom-lens { position: absolute; border: 1px solid #d4d4d4; /*set the size of the lens:*/ width: 40px; height: 40px; } .img-zoom-result { border: 1px solid #d4d4d4; /*set the size of the result div:*/ width: 300px; height: 300px; }
3단계) 자바스크립트 추가
function imageZoom(imgID, resultID) { var img, lens, result, cx, cy; img = document.getElementById(imgID); result = document.getElementById(resultID); /* Create lens: */ lens = document.createElement("DIV"); lens.setAttribute("class", "img-zoom-lens"); /* Insert lens: */ img.parentElement.insertBefore(lens, img); /* Calculate the ratio between result DIV and lens: */ cx = result.offsetWidth / lens.offsetWidth; cy = result.offsetHeight / lens.offsetHeight; /* Set background properties for the result DIV */ result.style.backgroundImage = "url('" + img.src + "')"; result.style.backgroundSize = (img.width * cx) + "px " + (img.height * cy) + "px"; /* Execute a function when someone moves the cursor over the image, or the lens: */ lens.addEventListener("mousemove", moveLens); img.addEventListener("mousemove", moveLens); /* And also for touch screens: */ lens.addEventListener("touchmove", moveLens); img.addEventListener("touchmove", moveLens); function moveLens(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); /* Calculate the position of the lens: */ x = pos.x - (lens.offsetWidth / 2); y = pos.y - (lens.offsetHeight / 2); /* Prevent the lens from being positioned outside the image: */ if (x > img.width - lens.offsetWidth) {x = img.width - lens.offsetWidth;} if (x < 0) {x = 0;} if (y > img.height - lens.offsetHeight) {y = img.height - lens.offsetHeight;} if (y < 0) {y = 0;} /* Set the position of the lens: */ lens.style.left = x + "px"; lens.style.top = y + "px"; /* Display what the lens "sees": */ result.style.backgroundPosition = "-" + (x * cx) + "px -" + (y * cy) + "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}; } }
4단계) 확대/축소 효과 시작
<script> imageZoom("myimage", "myresult"); </script>
기본 예시
예제 보기참고
W3C School - How TO - Image Zoom