JavaScript實現簡易放大鏡最全程式碼解析(ES5)
阿新 • • 發佈:2021-09-10
本文例項為大家分享了實現簡易放大鏡的具體程式碼,供大家參考,具體內容如下
完整程式碼:
<!DOCTYPE html> <html> <hwww.cppcns.comead> <meta charset="UTF-8"> <title>ES5放大鏡</title> <http://www.cppcns.com;style> .box { width: 170px; height: 180px; margin: 100px 200px; border: 1px solid #ccc; position: relative; } .small { position: relative; } .big { width: 300px; height: 320px; position: absolute; top: 30px; left: 220px; overflow: hidden; border: 1px solid #ccc; display: none; } .mask { width: 100px; height: 100px; background: rgba(255,255,0.3); position: absolute; top: 0; left: 0; cursor: move; display: none; } .big img{ position: absolute; left: 0; top: 0; } </style> </head> <body> <div class="box" id="box"> <div class="small"> <img src="img/shirt_1.jpg" alt="picture"/> <div class="mask"></div> </div> <div class="big"> <img src="img/shirt_1_big.jpg" alt="picture"/> </div> </div> </body> <script> var box = document.getElementById('box'); var small = box.children[0UReWHzjW];//放小圖的盒子 var big = box.children[1];//放大圖的盒子 var mask = small.children[1];//半透明滑鼠移動跟隨盒子 var bigImage = big.children[0];//大圖片 small.onmouseover = function(event){ big.style.display = 'block'; mask.style.display = 'block'; } small.onmouseout = function(){ big.style.display = 'none'; mask.style.display = 'none'; } //移動事件,注意mask的定位相對的是samll small.onmousemove = function(event){ var event = event || window.event;//事件物件 // console.log(this.offsetLeft);//0,注意offsetLeft返回距離是一個帶有定位的父級的左側距離 var x = event.clientX-this.offsetParent.offsetLeft-mask.offsetWidth/2;//此處不能用small的offsetLeft,用obj的offsetLeft var y = event.clientY-this.offsetParent.offsetTop-mask.offsetHeight/2; //限制半透明盒子出界 if(x < 0){ x = 0; }else if(x > small.offsetWidth - mask.offsetWidth){ x = small.offsetWidth - mask.offsetWidth; } if( y < 0){ y = 0; }else if( y > small.offsetHeight - mask.offsetHeight){ y = small.offsetHeight - mask.offsetHeight; } mask.style.left = x + "px"; mask.style.top = y +"px"; //大圖片放大 bigImage.style.left = -x*big.offsetWidth/small.offsetWidth + 'px'; bigImage.style.top = -y*big.offsetHeight/small.offsetHeight + 'px'; //big.offsetWidth/small.offsetWidth是放大倍數 //因為小圖滑鼠下移,大圖上移,故用負數 } </script> </html>
圖片:
以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支援我們。