多级关联下拉选择框的高效完成1

<BODY>
<SELECT NAME="s1"><option>需要JavaScript才能正确显示</SELECT>
<SELECT NAME="s2"></SELECT>
<SELECT NAME="s3"></SELECT>
<SELECT NAME="s4"></SELECT>

<SCRIPT LANGUAGE="JavaScript">
<!--

//选择框的名字
selector = [ "s1", "s2", "s3", "s4" ];

//选择项: "名字", "值", 子选择
menu = [
"地球","1",
[
"中国","86",
  [
  "北京","BJ",
   [
   "--","1",null
   ],
  "四川","SC",
   [
   "成都","28",null,
   "乐山","",null,
   "攀枝花","",null,
   "自贡","",null,
   "德阳","",null,
   "绵阳","",null
   ]
  ],
"米国","1",
  [
  "加利福尼亚","CA",
   [
   "旧金山","1",null,
   "洛杉矶","2",null
   ],
  "华盛顿","WA",
   [
   "西雅图","seattle",null
   ]
  ]
],
"火星","2",
[
"大峡谷","86",
  [
  "小山丘","BJ",
   [
   "A地区","28",null,
   "B地区","",null,
   "C地区","",null
   ]
  ]
]
];

function wizz(level)
{
if( level == 0 )
  a = menu;
else
{
  str = "menu";
  for( i=0; i<level; i++ )
   str += "[" + (document.all[selector[i]].selectedIndex * 3 + 2) + "]";
  a = eval(str);
}
if( a == null ) return;

s = document.all[selector[level]];
i = s.length;
while( i > 0 ) s.options[--i] = null;
while( i < Math.floor(a.length/3) )
  s.options[i] = Option( a[i*3], a[i++*3+1] );
s.onchange = Function("wizz(" + (level+1) + ")");
wizz(level+1);
}

wizz(0);

//-->
</SCRIPT>

</BODY>
</HTML>

……

标签:多级关联下拉选择框的高效完成