<input type="image" border="0" align=middle height=20 id=IMG1 name="IMG1" onclick="javascript:OnSearch()" disabled=true style="CURSOR: hand" width=40 src="http://expert.csdn.net/images/top1.gif"><input type=button value=" disabled=false" onclick="javascript:IMG1.disabled=false">
style="CURSOR: hand" width=40 >
<input type=checkbox onclick="IMG1.disabled=!this.checked;">可能是楼主的页面里有一个以上的对象name为IMG1