原创JS图片放大查看效果(兼容IE,FF)

<script language="JavaScript">

<!--

var smallX = 200; //缩略图宽度

var bigX = 600; //预览窗大小,可以任意设置

var bigY = 450;

var srcX = -1; //原图大小,可以任意设置. 如都为-1将使用图片原始大小

var srcY = -1;

var border = 5; //边框

var smallY,viewX,viewY,bl,isIE,vX,vY;

window.onload=function (){

        head.innerHTML="图片已载入";

        isIE=window.event?1:0;

        if (srcX==-1 && srcY==-1){srcX=bigpic.width;srcY=bigpic.height;}

        else{bigpic.width=srcX;bigpic.height=srcY;}

        smallY=srcY*smallX/srcX;

        viewX=bigX/srcX*smallX; //预览范围

        viewY=bigY/srcY*smallY;

        bl=srcX/smallX; //缩小比例

        smallpic.width=smallX;

        smallpic.height=smallY;

        smallbox.style.borderWidth=border;

        smallbox.style.width=smallpic.offsetWidth+border*2*isIE;

        smallbox.style.height=smallpic.offsetHeight+border*2*isIE;

        bigbox.style.borderWidth=border;

        bigbox.style.width=bigX+border*2*isIE;

        bigbox.style.height=bigY+border*2*isIE;

        view.style.left=smallbox.offsetLeft + border;

        view.style.top=smallbox.offsetTop + border;

        view.style.width=viewX- !isIE*3+1;

        view.style.height=viewY- !isIE*3+1;

}

function move(e){

        var e = window.event?window.event:e;

        if (!isIE){vX=e.pageX-border-smallbox.offsetLeft;

        vY=e.pageY-border-smallbox.offsetTop}

        else{vX=e.offsetX;vY=e.offsetY}

        vX+=-viewX/2;

        vY+=-viewY/2;

        if (vX < 0) vX = 0;

        if (vY < 0) vY = 0;

        if (vX > smallX - viewX) vX = smallX - viewX;

        if (vY > smallY - viewY) vY = smallY - viewY;

        bigpico.style.marginLeft = - vX * bl;

        bigpico.style.marginTop = - vY * bl;

        view.style.left = vX + smallbox.offsetLeft + border;

        view.style.top = vY + smallbox.offsetTop + border;

}

//-->

</script>

<style type="text/css">

<!--

*{padding:0;margin:0}

body{background:black}

img{display:block;}

#smallbox{border:1px #c33 solid;float:left;width:0;height:0;

   overflow:hidden;font-size:0px}

#bigbox{border:1px #c33 solid;width:0px;height:0px;float:left;

   overflow:hidden;font-size:0px}

#view{border:1px #ddd solid;width:0px;height:0px;

   position:absolute;font-size:0px}

#head{text-align:center;line-height:40px;font:bold 16px/40px;color:pink}

//-->

</style>

<div id="head">图片loading...</div>

<div id="smallbox"><img id="smallpic"

src="http://images2.wowchina.com/images_wow/download/wallpapers/2007/11/7/55591.jpg"

border="0" onmousemove="move(event)"></div>

<div id="bigbox"><div id="bigpico"><img id="bigpic"

src="http://images2.wowchina.com/images_wow/download/wallpapers/2007/11/7/55591.jpg"

border="0"></div></div>

<div id="view" onmousemove="if (!isIE) move(event)"></div>