function ChangeLayer(str) 
{ 
	var table_num = "12";

	for(i=1; i<=table_num; i++){ 

		str1 = eval("document.all.div0" + i ); 

		if(i == str){ 
		str1.style.display = "block"; 
		}else{ 
			str1.style.display = "none"; 
		} 

	} 
}