如何保持（绝对）页脚在底部？-Howtokeep(absolute)footeratthebottom?

I want to keep my footer at the bottom of the page while keeping there position absolute , the have the following page structure :

我希望将页脚保持在页面底部,同时保持绝对位置,具有以下页面结构:

 
 //want to keep its size auto and always on the top (position absolute) 
 
 //the children of #body have position absolute (keep size auto)
 
 //want to keep this at the bottom (just below body , if body size 
                         changes then footer will also change (position absolute)

How can i do this?

我怎样才能做到这一点?

Edit

I think i was not clear to my question, sorry for that but my actual problem is that in #main ( height : auto ) the contents are absolute so those contents are not included in the height of main ( i am just guessing this ) thats why the height of main was 0 because of this the footer comes up. This is my actual problem.

我想我不清楚我的问题,对不起,但我的实际问题是在#main(高度:自动)内容是绝对的,所以这些内容不包括在主的高度(我只是猜测这个)那是为什么主要的高度是0因为这个页脚出现了。这是我的实际问题。

2 个解决方案

#foot {
  position:absolute; /* your requirement, you can also use fixed though */
  bottom:0;
  /* your other possible styles */
}

#head {
    position:fixed;
    height:30px;
    top:0;
    left:0;
    right:0;
}
#foot{
    position:fixed;
    height:40px;
    bottom:0;
    left:0;
    right:0;
}

#body{
    padding-top:30px; /* the same as the #head height*/
    padding-bottom:40px; /* the same as the #foot height*/
}