IE6中的position:fixed定位兼容性写法分享

/ 修正IE6振动bug /
html, html body{background-image:url(about:blank);background-attachment:fixed;}
/ IE6 头部固定 /
html .fixed-{position:absolute;bottom:auto;:expression(eval(document.documentElement.scrollTop));}
/ IE6 右侧固定 /
html .fixed-right{position:absolute;right:auto;left:expression(eval(document.documentElement.scrollLeft+document.documentElement.clientWidth-this.offsetWidth)-(parseInt(this.currentStyle.marginLeft,10)||0)-(parseInt(this.currentStyle.marginRight,10)||0));}
/ IE6 底部固定 /
html .fixed-bottom{position:absolute;bottom:auto;:expression(eval(document.documentElement.scrollTop+document.documentElement.clientHeight-this.offsetHeight-(parseInt(this.currentStyle.marginTop,10)||0)-(parseInt(this.currentStyle.marginBottom,10)||0)));}
/ IE6 左侧固定 /
html .fixed-left{position:absolute;right:auto;left:expression(eval(document.documentElement.scrollLeft));}