2.鼠标事件坐标获取
function fnDown(event) { var event = event || window.event; var oDrag = document.getElementById("loginPanel"); //光标按下时光标和面板之间的距离; var disX = event.clientX - oDrag.offsetLeft; var disY = event.clientY - oDrag.offsetTop; //移动 document.onmousemove = function (event) { event = event || window.event; fnMove(event, disX, disY); }; document.onmouseup = function () { document.onmousemove = null; document.onmouseup = null; } } function fnMove(event, posX, posY) { var oDrag = document.getElementById("loginPanel"); var l = event.clientX - posX; var t = event.clientY - posY; var winW = document.documentElement.clientWidth; var winH = document.documentElement.clientHeight; var maxW = winW - oDrag.offsetWidth - 10; var maxH = winH - oDrag.offsetHeight; //当l=0时,窗口不能继续外移 if (l < 0) { l = 0; } else if (l > maxW) { l = maxW; } if (t < 10) { t = 10; } else if (t > maxH) { t = maxH; } oDrag.style.left = l + "px"; oDrag.style.top = t + "px"; }
3.封装各浏览器通用的getElementsByClassName()方法
方法返回的是一个数组,切记
function getByClass(clsName, parent) { var oParent = parent ? document.getElementById(parent) : document, eles = [], elements = oParent.getElementsByTagName('*'); for (var i = 0, l = elements.length; i < l; i++) { if (elements[i].className == clsName) { eles.push(elements[i]); } } return eles; }