鼠標事件 · JavaScript學習記錄

### 鼠標事件 - 鼠標位置 - 可視區位置：`clientX`、`clientY` - 例子：跟隨鼠標的 `Div` - 消除滾動條的影響：**可視區**與**頁面頂部**的距離 - 代碼： ```js // 封裝鼠標當前坐標函數 function getPos(ev) { var scrollTop = document.documentElement.scrollTop||document.body.scrollTop; var scrollLeft = document.documentElement.scollLeft||document.body.scrollLeft; return {x: ev.clientX+scrollLeft, y: ev.clientY+scrollTop}; } ``` - 滾輪事件：`onmousewheel` 滾輪數據：`event.wheelDelta` - 代碼：鼠標滾輪控制 `div` 移動 ```HTML <!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html;charset=UTF-8"> <title>事件綁定與鼠標滾輪</title> <link rel="stylesheet" href="../reset.css"> <style> #div1 { width: 200px; height: 200px; position: absolute; background-color: rgb(255, 0, 0); } </style> <script type="text/javascript"> var iDis = 0; var scrollFunc = function (e) { var oDiv1 = document.getElementById('div1'); e = e || window.event; if (e.wheelDelta) { //判斷瀏覽器IE，谷歌滑輪事件 if (e.wheelDelta > 0) { //當滑輪向上滾動時 iDis += -e.wheelDelta; oDiv1.style.top = iDis/12 + 'px'; console.log("滑輪向上滾動",e.wheelDelta, iDis, oDiv1.offsetTop); } if (e.wheelDelta < 0) { //當滑輪向下滾動時 iDis += -e.wheelDelta; oDiv1.style.top = iDis/12 + 'px'; console.log("滑輪向上滾動",e.wheelDelta, iDis, oDiv1.offsetTop); } } else if (e.detail) { //Firefox滑輪事件 if (e.detail> 0) { //當滑輪向上滾動時 console.log("滑輪向上滾動",e.wheelDelta); } if (e.detail< 0) { //當滑輪向下滾動時 console.log("滑輪向下滾動",e.wheelDelta); } } } //給頁面綁定滑輪滾動事件 if (document.addEventListener) {//firefox document.addEventListener('DOMMouseScroll', scrollFunc, false); } //滾動滑輪觸發scrollFunc方法 //ie 谷歌 window.onmousewheel = document.onmousewheel = scrollFunc; </script> </head> <body> <div id="div1"></div> </body> </html> ``` - 獲取鼠標在頁面的絕對位置 - 封裝函數 - 例子：一串跟隨鼠標的 `Div` - 代碼： ```HTML <!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html;charset=UTF-8"> <title>跟隨鼠標的一串div</title> <link rel="stylesheet" href="../reset.css"> <style> div { width: 10px; height: 10px; position: absolute; background-color: rgb(255, 0, 0); } </style> <script> window.onload = function () { // 封裝鼠標當前坐標函數 function getPos(ev) { var scrollTop = document.documentElement.scrollTop||document.body.scrollTop; var scrollLeft = document.documentElement.scollLeft||document.body.scrollLeft; return {x: ev.clientX+scrollLeft, y: ev.clientY+scrollTop}; } var oDiv = document.getElementsByTagName('div'); document.onmousemove = function () { var ev = ev || event; // 后一個元素跟隨前一個元素 for ( var i = oDiv.length-1; i > 0; i--) { console.log(oDiv[i].style.left,oDiv[i-1].offsetLeft) oDiv[i].style.left = oDiv[i-1].offsetLeft + 'px'; oDiv[i].style.top = oDiv[i-1].offsetTop + 'px'; } // 當前多變賦值給第一個元素， var pos = getPos(ev); oDiv[0].style.left = pos.x + 'px'; oDiv[0].style.top = pos.y + 'px'; } } </script> </head> <body> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> <div></div><div></div><div></div><div></div><div></div> </body> </html> ```