很多網友曾問過這個效果，我做了一個小例子放在CSDN的博客里面,地址是：
http://download.csdn.net/user/chenpeng0118
if (typeof document.attachEvent!='undefined') {
window.attachEvent('onload',init);
document.attachEvent('onmousemove',moveMouse);
document.attachEvent('onclick',checkMove); }
else {
window.addEventListener('load',init,false);
document.addEventListener('mousemove',moveMouse,false);
document.addEventListener('click',checkMove,false);
}
var oDv=document.createElement("div");
var dvHdr=document.createElement("div");
var dvBdy=document.createElement("div");
var windowlock,boxMove,fixposx,fixposy,lockX,lockY,fixx,fixy,ox,oy,boxLeft,boxRight,boxTop,boxBottom,evt,mouseX,mouseY,boxOpen,totalScrollTop,totalScrollLeft;
boxOpen=false;
ox=10;
oy=10;
lockX=0;
lockY=0;
function init() {
oDv.appendChild(dvHdr);
oDv.appendChild(dvBdy);
oDv.style.position="absolute";
oDv.style.visibility='hidden';
document.body.appendChild(oDv);
}
function defHdrStyle() {
dvHdr.innerHTML='<img style="vertical-align:middle" src="info.gif"> '+dvHdr.innerHTML;
dvHdr.style.fontWeight='';
dvHdr.style.width='100px';
dvHdr.style.fontFamily='arial';
dvHdr.style.border='1px solid #A5CFE9';
dvHdr.style.padding='3';
dvHdr.style.fontSize='11';
dvHdr.style.color='#ffffff';
dvHdr.style.background='CadetBlue';
dvHdr.style.filter='alpha(opacity=85)'; // IE
dvHdr.style.opacity='0.85'; // FF
}
function defBdyStyle() {
dvBdy.style.borderBottom='1px solid #A5CFE9';
dvBdy.style.borderLeft='1px solid #A5CFE9';
dvBdy.style.borderRight='1px solid #A5CFE9';
dvBdy.style.width='100px';
dvBdy.style.fontFamily='arial';
dvBdy.style.fontSize='11';
dvBdy.style.padding='3';
dvBdy.style.color='#1B4966';
dvBdy.style.background='#FFFFFF';
dvBdy.style.filter='alpha(opacity=85)'; // IE
dvBdy.style.opacity='0.85'; // FF
}
function checkElemBO(txt) {
if (!txt || typeof(txt) != 'string') return false;
if ((txt.indexOf('header')>-1)&&(txt.indexOf('body')>-1)&&(txt.indexOf('[')>-1)&&(txt.indexOf('[')>-1))
return true;
else
return false;
}
function scanBO(curNode) {
if (checkElemBO(curNode.title)) {
curNode.boHDR=getParam('header',curNode.title);
curNode.boBDY=getParam('body',curNode.title);
curNode.boCSSBDY=getParam('cssbody',curNode.title);
curNode.boCSSHDR=getParam('cssheader',curNode.title);
curNode.IEbugfix=(getParam('hideselects',curNode.title)=='on')?true:false;
curNode.fixX=parseInt(getParam('fixedrelx',curNode.title));
curNode.fixY=parseInt(getParam('fixedrely',curNode.title));
curNode.absX=parseInt(getParam('fixedabsx',curNode.title));
curNode.absY=parseInt(getParam('fixedabsy',curNode.title));
curNode.offY=(getParam('offsety',curNode.title)!='')?parseInt(getParam('offsety',curNode.title)):10;
curNode.offX=(getParam('offsetx',curNode.title)!='')?parseInt(getParam('offsetx',curNode.title)):10;
curNode.fade=(getParam('fade',curNode.title)=='on')?true:false;
curNode.fadespeed=(getParam('fadespeed',curNode.title)!='')?getParam('fadespeed',curNode.title):0.04;
curNode.delay=(getParam('delay',curNode.title)!='')?parseInt(getParam('delay',curNode.title)):0;
if (getParam('requireclick',curNode.title)=='on') {
curNode.requireclick=true;
document.all?curNode.attachEvent('onclick',showHideBox):curNode.addEventListener('click',showHideBox,false);
document.all?curNode.attachEvent('onmouseover',hideBox):curNode.addEventListener('mouseover',hideBox,false);
}
else {// Note : if requireclick is on the stop clicks are ignored
if (getParam('doubleclickstop',curNode.title)!='off') {
document.all?curNode.attachEvent('ondblclick',pauseBox):curNode.addEventListener('dblclick',pauseBox,false);
}
if (getParam('singleclickstop',curNode.title)=='on') {
document.all?curNode.attachEvent('onclick',pauseBox):curNode.addEventListener('click',pauseBox,false);
}
}
curNode.windowLock=getParam('windowlock',curNode.title).toLowerCase()=='off'?false:true;
curNode.title='';
curNode.hasbox=1;
}
else
curNode.hasbox=2;
}
function getParam(param,list) {
var reg = new RegExp('([^a-zA-Z]' + param + '|^' + param + ')//s*=//s*//[//s*(((
//[//[)|(//]//])|([^//]//[]))*)//s*//]'
);
var res = reg.exec(list);
var returnvar;
if(res)
return res[2].replace('[[','[').replace(']]',']');
else
return '';
}
function Left(elem){
var x=0;
if (elem.calcLeft)
return elem.calcLeft;
var oElem=elem;
while(elem){
if ((elem.currentStyle)&& (!isNaN(parseInt(elem.currentStyle.borderLeftWidth)))&&(x!=0))
x+=parseInt(elem.currentStyle.borderLeftWidth);
x+=elem.offsetLeft;
elem=elem.offsetParent;
}
oElem.calcLeft=x;
return x;
}
function Top(elem){
var x=0;
if (elem.calcTop)
return elem.calcTop;
var oElem=elem;
while(elem){
if ((elem.currentStyle)&& (!isNaN(parseInt(elem.currentStyle.borderTopWidth)))&&(x!=0))
x+=parseInt(elem.currentStyle.borderTopWidth);
x+=elem.offsetTop;
elem=elem.offsetParent;
}
oElem.calcTop=x;
return x;
}
var ah,ab;
function applyStyles() {
if(ab)
oDv.removeChild(dvBdy);
if (ah)
oDv.removeChild(dvHdr);
dvHdr=document.createElement("div");
dvBdy=document.createElement("div");
CBE.boCSSBDY?dvBdy.className=CBE.boCSSBDY:defBdyStyle();
CBE.boCSSHDR?dvHdr.className=CBE.boCSSHDR:defHdrStyle();
dvHdr.innerHTML=CBE.boHDR;
dvBdy.innerHTML=CBE.boBDY;
ah=false;
ab=false;
if (CBE.boHDR!='') {
oDv.appendChild(dvHdr);
ah=true;
}
if (CBE.boBDY!=''){
oDv.appendChild(dvBdy);
ab=true;
}
}
var CSE,iterElem,LSE,CBE,LBE, totalScrollLeft, totalScrollTop, width, height ;
var ini=false;
// Customised function for inner window dimension
function SHW() {
if (document.body && (document.body.clientWidth !=0)) {
width=document.body.clientWidth;
height=document.body.clientHeight;
}
if (document.documentElement && (document.documentElement.clientWidth!=0) && (document.body.clientWidth + 20 >= document.documentElement.clientWidth)) {
width=document.documentElement.clientWidth;
height=document.documentElement.clientHeight;
}
return [width,height];
}
var ID=null;
function moveMouse(e) {
//boxMove=true;
e?evt=e:evt=event;
CSE=evt.target?evt.target:evt.srcElement;
if (!CSE.hasbox) {
// Note we need to scan up DOM here, some elements like TR don't get triggered as srcElement
iElem=CSE;
while ((iElem.parentNode) && (!iElem.hasbox)) {
scanBO(iElem);
iElem=iElem.parentNode;
}
}
if ((CSE!=LSE)&&(!isChild(CSE,dvHdr))&&(!isChild(CSE,dvBdy))){
if (!CSE.boxItem) {
iterElem=CSE;
while ((iterElem.hasbox==2)&&(iterElem.parentNode))
iterElem=iterElem.parentNode;
CSE.boxItem=iterElem;
}
iterElem=CSE.boxItem;
if (CSE.boxItem&&(CSE.boxItem.hasbox==1)) {
LBE=CBE;
CBE=iterElem;
if (CBE!=LBE) {
applyStyles();
if (!CBE.requireclick)
if (CBE.fade) {
if (ID!=null)
clearTimeout(ID);
ID=setTimeout("fadeIn("+CBE.fadespeed+")",CBE.delay);
}
else {
if (ID!=null)
clearTimeout(ID);
COL=1;
ID=setTimeout("oDv.style.visibility='visible';ID=null;",CBE.delay);
}
if (CBE.IEbugfix) {hideSelects();}
fixposx=!isNaN(CBE.fixX)?Left(CBE)+CBE.fixX:CBE.absX;
fixposy=!isNaN(CBE.fixY)?Top(CBE)+CBE.fixY:CBE.absY;
lockX=0;
lockY=0;
boxMove=true;
ox=CBE.offX?CBE.offX:10;
oy=CBE.offY?CBE.offY:10;
}
}
else if (!isChild(CSE,dvHdr) && !isChild(CSE,dvBdy) && (boxMove)){
// The conditional here fixes flickering between tables cells.
if ((!isChild(CBE,CSE)) || (CSE.tagName!='TABLE')) {
CBE=null;
if (ID!=null)
clearTimeout(ID);
fadeOut();
showSelects();
}
}
LSE=CSE;
}
else if (((isChild(CSE,dvHdr) || isChild(CSE,dvBdy))&&(boxMove))) {
totalScrollLeft=0;
totalScrollTop=0;
iterElem=CSE;
while(iterElem) {
if(!isNaN(parseInt(iterElem.scrollTop)))
totalScrollTop+=parseInt(iterElem.scrollTop);
if(!isNaN(parseInt(iterElem.scrollLeft)))
totalScrollLeft+=parseInt(iterElem.scrollLeft);
iterElem=iterElem.parentNode;
}
if (CBE!=null) {
boxLeft=Left(CBE)-totalScrollLeft;
boxRight=parseInt(Left(CBE)+CBE.offsetWidth)-totalScrollLeft;
boxTop=Top(CBE)-totalScrollTop;
boxBottom=parseInt(Top(CBE)+CBE.offsetHeight)-totalScrollTop;
doCheck();
}
}
if (boxMove&&CBE) {
// This added to alleviate bug in IE6 w.r.t DOCTYPE
bodyScrollTop=document.documentElement&&document.documentElement.scrollTop?document.documentElement.scrollTop:document.body.scrollTop;
bodyScrollLet=document.documentElement&&document.documentElement.scrollLeft?document.documentElement.scrollLeft:document.body.scrollLeft;
mouseX=evt.pageX?evt.pageX-bodyScrollLet:evt.clientX-document.body.clientLeft;
mouseY=evt.pageY?evt.pageY-bodyScrollTop:evt.clientY-document.body.clientTop;
if ((CBE)&&(CBE.windowLock)) {
mouseY < -oy?lockY=-mouseY-oy:lockY=0;
mouseX < -ox?lockX=-mouseX-ox:lockX=0;
mouseY > (SHW()[1]-oDv.offsetHeight-oy)?lockY=-mouseY+SHW()[1]-oDv.offsetHeight-oy:lockY=lockY;
mouseX > (SHW()[0]-dvBdy.offsetWidth-ox)?lockX=-mouseX-ox+SHW()[0]-dvBdy.offsetWidth:lockX=lockX;
}
oDv.style.left=((fixposx)||(fixposx==0))?fixposx:bodyScrollLet+mouseX+ox+lockX+"px";
oDv.style.top=((fixposy)||(fixposy==0))?fixposy:bodyScrollTop+mouseY+oy+lockY+"px";
}
}
function doCheck() {
if ( (mouseX < boxLeft) || (mouseX >boxRight) || (mouseY < boxTop) || (mouseY > boxBottom)) {
if (!CBE.requireclick)
fadeOut();
if (CBE.IEbugfix) {showSelects();}
CBE=null;
}
}
function pauseBox(e) {
e?evt=e:evt=event;
boxMove=false;
evt.cancelBubble=true;
}
function showHideBox(e) {
oDv.style.visibility=(oDv.style.visibility!='visible')?'visible':'hidden';
}
function hideBox(e) {
oDv.style.visibility='hidden';
}
var COL=0;
var stopfade=false;
function fadeIn(fs) {
ID=null;
COL=0;
oDv.style.visibility='visible';
fadeIn2(fs);
}
function fadeIn2(fs) {
COL=COL+fs;
COL=(COL>1)?1:COL;
oDv.style.filter='alpha(opacity='+parseInt(100*COL)+')';
oDv.style.opacity=COL;
if (COL<1)
setTimeout("fadeIn2("+fs+")",20);
}
function fadeOut() {
oDv.style.visibility='hidden';
}
function isChild(s,d) {
while(s) {
if (s==d)
return true;
s=s.parentNode;
}
return false;
}
var cSrc;
function checkMove(e) {
e?evt=e:evt=event;
cSrc=evt.target?evt.target:evt.srcElement;
if ((!boxMove)&&(!isChild(cSrc,oDv))) {
fadeOut();
if (CBE&&CBE.IEbugfix) {showSelects();}
boxMove=true;
CBE=null;
}
}
function showSelects(){
var elements = document.getElementsByTagName("select");
for (i=0;i< elements.length;i++){
elements[i].style.visibility='visible';
}
}
function hideSelects(){
var elements = document.getElementsByTagName("select");
for (i=0;i< elements.length;i++){
elements[i].style.visibility='hidden';
}
}
