function huan(k)
{
			for(i=1; i<=5; i++){
				document.getElementById("huan"+i).className="cp_bt_a";
				/*document.getElementById("huan"+i).style.display="none";*/
			}
			document.getElementById("huan"+k).className="cp_bt_b";
			/*document.getElementById("huan"+k).style.display="block";*/
			document.getElementById("cpimage").src="../../img/"+k+".jpg";
}

<!--
	var pp=1;
	var nowgo = 1;
	function toDC(){
		document.getElementById('toLY').innerHTML="<textarea name='lycontent' id='lycontent' rows='2' cols='65'></textarea> <!-- 发送>> --><input type='submit' value='发送'>";
	}
	
	var top_pic = new Array();
	var top_p1 = new Array();
	var top_p2 = new Array();
	var top_link_all = new Array();
	//728x269 
	top_pic[1]="../../img/adv1.jpg";
	top_pic[2]="../../img/adv2.jpg";
	top_pic[3]="../../img/adv3.jpg";
	top_pic[4]="../../img/adv4.jpg";
	top_pic[5]="../../img/adv5.jpg";
	
	top_p1[1]="../jdn1a.jpg";
	top_p1[2]="../jdn2b.jpg";
	top_p1[3]="../jdn3c.jpg";
	top_p1[4]="../jdn4d.jpg";

	top_p2[1]="../jdn1.jpg";
	top_p2[2]="../jdn2.jpg";
	top_p2[3]="../jdn3.jpg";
	top_p2[4]="../jdn4.jpg";
	
	top_link_all[1] = "cpzx_sub.asp?lb=139";
	top_link_all[2] = "cpzx_sub.asp?lb=140";
	top_link_all[3] = "cpzx_sub.asp?lb=141";
	top_link_all[4] = "cpzx_sub.asp?lb=142";
	top_link_all[5] = "cpzx_sub.asp?lb=143";
	

	function top_mouse_move(str,n){
		for(var i=1;i<6;i++){
			document.getElementById("topT"+i).className="cp_bt_a";
		}
		if(document.all){
			document.getElementById('show_top_pic').filters.item(0).Stop();
			document.getElementById('show_top_pic').filters.item(0).transition = 23;
			document.getElementById('show_top_pic').filters.item(0).Apply();
		}
		document.getElementById('show_top_pic').src=top_pic[n];
		if(document.all){
			document.getElementById('show_top_pic').filters.item(0).Play();
		}
		document.getElementById('show_link').href=top_link_all[n];
		document.getElementById(str).className="cp_bt_b";
		pp=n;
	}
	function top_mouse_out(str){
		for(var i=1;i<5;i++){
			document.getElementById("topT"+i).className="cp_bt_a";
		}
		nowgo = 1;
	}
	function top_auto(){
		if(nowgo){
			top_mouse_out("topT"+pp);
			top_mouse_move("topT"+pp,pp);
		
			pp++;
			if(pp>5){pp=1;}
		}
	}
//-->