css样式中position和_position的区别
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" alt="" />
position:fixed; 相对于浏览器窗口绝对定位。
_position:absolute; 只有IE6能识别, IE6不支持fixed, 所以针对IE6使用absolute绝对定位, 一般还要配套一个expression脚本来实现
属性expression_r:针对ie6写的
CSS的出现使网页制作者在对网页元素的控制方便许多,当然,有利必有弊,CSS只能对颜色、大小、距离等静态样式有效,对于要实现某些html元素的动态样式就显得有些力不从心。
有了CSS的自定义属性expression_r,可以自己定义属性,自己在属性里写需要的代码,这样就可以结合CSS的特性与JS特效,实现对整体页面上相同元素的控制。
先用怎么消除页面上的链接虚线框为例。
通常的做法是:
link1
link2
link3
粗看或许还体现不出采用expression_r的优势,但如果你的页面上有几十甚至上百个链接,这时的你难道还会机械式地Ctrl+C,Ctrl+V么,何况两者一比较,哪个产生的冗余代码更多呢?采用expression_r的做法如下:
<style type="text/css">
a {star : expression_r(onfocus=this.blur)}
</style>
说明:里面的star就是自己任意定义的属性,你可以随自己喜好另外定义,接着包含在expression_r()里的语句就是JS脚本,在自定义属性与expression_r之间可别忘了还有一个引号,因为实质还是CSS,所以放在style标签内,而非script内。OK,这样就很容易地用一句话实现了页面中的链接虚线框的消除。不过你先别得意,如果触发的特效是CSS的属性变化,那么出来的结果会跟你的本意有差别。例如你想随鼠标的移进移出而改变页面中的文本框颜色更改,你可能想当然的会认为应该写为
<style type="text/css">
input {star : expression_r(onmouseover=this.style.backgroundColor="#FF0000";
onmouseout=this.style.backgroundColor="#FFFFFF")}
</style>
<input type="text">
<input type="text">
<input type="text">
可结果却是出现脚本出错,正确的写法应该把CSS样式的定义写进函数内,如下所示:
<style type="text/css">
input {star : expression_r(onmouseover=function()
{this.style.backgroundColor="#FF0000"},
onmouseout=function(){this.style.backgroundColor="#FFFFFF"}
)
}
</style> <input type="text">
<input type="text">
<input type="text">
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