怎样使可编辑的DIV固定大小，当内容多时，就自动出现滚动条

方法一

<style
type="text/css">

#Composition{

BORDER-RIGHT: #fff 2px
inset;

PADDING-RIGHT: 5px;

BORDER-TOP: #fff 2px inset;

PADDING-LEFT:
5px;

color: #000000;

BACKGROUND: white;

PADDING-BOTTOM:
5px;

OVERFLOW: auto;

BORDER-LEFT: #fff 2px inset;

PADDING-TOP:
5px;

BORDER-BOTTOM: #fff 2px inset;

}

</style>

<div ID="Composition" name="Composition" style="WIDTH: 100%;
HEIGHT: 400px">在线编辑器</div>

方法二

<style
type="text/css">

#Composition{

BORDER-RIGHT: #fff 2px
inset;

PADDING-RIGHT: 5px;

BORDER-TOP: #fff 2px inset;

PADDING-LEFT:
5px;

color: #000000;

BACKGROUND: white;

PADDING-BOTTOM:
5px;

OVERFLOW: auto;

BORDER-LEFT: #fff 2px inset;

PADDING-TOP:
5px;

BORDER-BOTTOM: #fff 2px inset;

}

</style>

<div ID="Composition" contentEditable="true"  name="Composition"
style="WIDTH: 100%; HEIGHT: 400px">在线编辑器</div>