放大镜

第一步:把如下代码加入<body>区域中
<STYLE type=text/css>#mglass {
LEFT: -2000px; POSITION: absolute; TOP: 50px
}
#thumb {
LEFT: -2000px; POSITION: absolute; TOP: 50px
}
#large {
LEFT: -2000px; POSITION: absolute; TOP: 50px
}
#framegif {
LEFT: -2000px; POSITION: absolute; TOP: 50px
}
.baseline {
COLOR: #000000; FONT-FAMILY: Arial; FONT-SIZE: 9pt; LEFT: 50px; POSITION: absolute; TOP: 260px
}
</STYLE>
<SCRIPT language=JavaScript>
<!-- Beginning of JavaScript -
var isNav, isIE
var offsetX, offsetY
var selectedObj

var enlargefactor=5
//修改放大的图像位置
var largewidth = 455
var largeheight = 523
var largeleft = 250
var largetop = 30
//修改缩小的图像位置
var thumbwidth = Math.floor(largewidth/enlargefactor)
var thumbheight = Math.floor(largeheight/enlargefactor)
var thumbleft = 50
var thumbtop = 30
//修改放大块的大小和位置
var mglasswidth = 32
var mglassheight = 32
var mglassleft = 120
var mglasstop = 110

var difleft= largeleft-thumbleft
var diftop= largetop-thumbtop

var clippoints

var cliptop = (thumbheight-mglassheight)*enlargefactor
var clipbottom = cliptop+(mglassheight*enlargefactor)
var clipleft =(thumbwidth-mglasswidth)*enlargefactor
var clipright = clipleft+(mglasswidth*enlargefactor)

if (parseInt(navigator.appVersion) >= 4) {
if (navigator.appName == "Netscape") {
isNav = true
} else {
isIE = true
}
}

function setZIndex(obj, zOrder) {
obj.zIndex = zOrder
}

function shiftTo(obj, x, y) {
if (isNav) {
  obj.moveTo(x,y)
} else {
  obj.pixelLeft = x
  obj.pixelTop = y
}
cliptop = (y-thumbtop)*enlargefactor
clipbottom = cliptop+(mglassheight*enlargefactor)
clipleft = (x-thumbleft)*enlargefactor
clipright = clipleft+(mglasswidth*enlargefactor)

if (document.all) {
  clippoints ="rect("+cliptop+" "+clipright+" "+clipbottom+" "+clipleft+")"
  document.all.large.style.posTop=largetop-cliptop
  document.all.large.style.posLeft=largeleft-clipleft
  document.all.large.style.clip=clippoints
}
if (document.layers) {
  document.large.top=largetop-cliptop
  document.large.left=largeleft-clipleft
  document.large.clip.left = clipleft
  document.large.clip.right = clipright
  document.large.clip.top = cliptop
  document.large.clip.bottom = clipbottom
}
}

function setSelectedElem(evt) {
if (isNav) {
  var testObj
  var clickX = evt.pageX
  var clickY = evt.pageY
  for (var i = document.layers.length - 1; i >= 0; i--) {
   testObj = document.layers[i]
   if ((clickX > testObj.left) &&
    (clickX < testObj.left + testObj.clip.width) &&
    (clickY > testObj.top) &&
    (clickY < testObj.top + testObj.clip.height)) {
     selectedObj = testObj
     setZIndex(selectedObj, 100)
     return
   }
  }
} else {
  var imgObj = window.event.srcElement
  if (imgObj.parentElement.id.indexOf("mglass") != -1) {
   selectedObj = imgObj.parentElement.style
   setZIndex(selectedObj,100)
   return
  }
}
selectedObj = null
return
}

function dragIt(evt) {
if (selectedObj) {
  if (isNav) {
   shiftTo(selectedObj, (evt.pageX - offsetX), (evt.pageY - offsetY))
  } else {
   shiftTo(selectedObj, (window.event.clientX - offsetX), (window.event.clientY - offsetY))
   return false
  }
}
}

function engage(evt) {
setSelectedElem(evt)
if (selectedObj) {
  if (isNav) {
   offsetX = evt.pageX - selectedObj.left
   offsetY = evt.pageY - selectedObj.top
  } else {
   offsetX = window.event.offsetX
   offsetY = window.event.offsetY
  }
}
return false
}

function release(evt) {
if (selectedObj) {
setZIndex(selectedObj, 0)
selectedObj = null
}
}

function setNavEventCapture() {
if (isNav) {
document.captureEvents(Event.MOUSEDOWN | Event.MOUSEMOVE | Event.MOUSEUP)
}
}

function init() {

if (document.layers) {
  document.large.left=largeleft
  document.large.top=largetop

  document.framegif.left=largeleft-3
  document.framegif.top=largetop-3

  document.thumb.left=thumbleft
  document.thumb.top=thumbtop

  document.mglass.left=mglassleft
  document.mglass.top=mglasstop

  document.large.clip.left = 0
  document.large.clip.right = 0
  document.large.clip.top = 0
  document.large.clip.bottom = 0

  setNavEventCapture()
}

if (document.all) {
  document.all.large.style.posLeft=largeleft
  document.all.large.style.posTop=largetop

  document.all.framegif.style.posLeft=largeleft-3
  document.all.framegif.style.posTop=largetop-3

  document.all.thumb.style.posLeft=thumbleft
  document.all.thumb.style.posTop=thumbtop

  document.all.mglass.style.posLeft=mglassleft
  document.all.mglass.style.posTop=mglasstop
  document.all.large.style.clip="rect(0 0 0 0)"
}

document.onmousedown = engage
document.onmousemove = dragIt
document.onmouseup = release
}
// - End of JavaScript - -->
</SCRIPT>
//修改图像位置，1、3是需放大的图像，2是放大框，4是放大镜
<span id=thumb><IMG name=thumbpic src="031.jpg" width=91>
</span>
<span id=framegif><IMG height=166 name=framepic src="frame2311.gif"
width=166> </span>
<span id=large><IMG name=largepic src="031.jpg" width=455>
</span>
<span id=mglass><IMG height=50 name=mglasspic src="mglass.gif"
width=50> </span>

第二步:修改<body***>中的内容，将下面的代码加入原<body***>中
onload=init()