asp.net实现二级联动

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    where[0] = new comefrom("请选择省份名", "请选择城市名");
    where[1] = new comefrom("北京", "|东城|西城|崇文|宣武|朝阳|丰台|石景山|海淀|门头沟|房山|通州|顺义|昌

平|大兴|平谷|怀柔|密云|延庆");
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山|松江|青浦|南汇|奉贤|崇明");
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港|宁河|静海|宝坻|蓟县");
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巴南|黔江|长寿|綦江|潼南|铜梁|大足|荣昌|壁山|梁平|城口|丰都|垫江|武隆|忠县|开县|云阳|奉节|巫山|巫溪|石柱|

秀山|酉阳|彭水|江津|合川|永川|南川");
    where[5] = new comefrom("河北", "|石家庄|邯郸|邢台|保定|张家口|承德|廊坊|唐山|秦皇岛|沧州|衡水");
    where[6] = new comefrom("山西", "|太原|大同|阳泉|长治|晋城|朔州|吕梁|忻州|晋中|临汾|运城");
    where[7] = new comefrom("内蒙古", "|呼和浩特|包头|乌海|赤峰|呼伦贝尔盟|阿拉善盟|哲里木盟|兴安盟|乌兰

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    where[8] = new comefrom("辽宁", "|沈阳|大连|鞍山|抚顺|本溪|丹东|锦州|营口|阜新|辽阳|盘锦|铁岭|朝阳|葫

芦岛");
    where[9] = new comefrom("吉林", "|长春|吉林|四平|辽源|通化|白山|松原|白城|延边");
    where[10] = new comefrom("黑龙江", "|哈尔滨|齐齐哈尔|牡丹江|佳木斯|大庆|绥化|鹤岗|鸡西|黑河|双鸭山|伊

春|七台河|大兴安岭");
    where[11] = new comefrom("江苏", "|南京|镇江|苏州|南通|扬州|盐城|徐州|连云港|常州|无锡|宿迁|泰州|淮安

");
    where[12] = new comefrom("浙江", "|杭州|宁波|温州|嘉兴|湖州|绍兴|金华|衢州|舟山|台州|丽水");
    where[13] = new comefrom("安徽", "|合肥|芜湖|蚌埠|马鞍山|淮北|铜陵|安庆|黄山|滁州|宿州|池州|淮南|巢湖

|阜阳|六安|宣城|亳州");
    where[14] = new comefrom("福建", "|福州|厦门|莆田|三明|泉州|漳州|南平|龙岩|宁德");
    where[15] = new comefrom("江西", "|南昌市|景德镇|九江|鹰潭|萍乡|新馀|赣州|吉安|宜春|抚州|上饶");
    where[16] = new comefrom("山东", "|济南|青岛|淄博|枣庄|东营|烟台|潍坊|济宁|泰安|威海|日照|莱芜|临沂|

德州|聊城|滨州|菏泽");
    where[17] = new comefrom("河南", "|郑州|开封|洛阳|平顶山|安阳|鹤壁|新乡|焦作|濮阳|许昌|漯河|三门峡|南

阳|商丘|信阳|周口|驻马店|济源");
    where[18] = new comefrom("湖北", "|武汉|宜昌|荆州|襄樊|黄石|荆门|黄冈|十堰|恩施|潜江|天门|仙桃|随州|

咸宁|孝感|鄂州");
    where[19] = new comefrom("湖南", "|长沙|常德|株洲|湘潭|衡阳|岳阳|邵阳|益阳|娄底|怀化|郴州|永州|湘西|

张家界");
    where[20] = new comefrom("广东", "|广州|深圳|珠海|汕头|东莞|中山|佛山|韶关|江门|湛江|茂名|肇庆|惠州|

梅州|汕尾|河源|阳江|清远|潮州|揭阳|云浮");
    where[21] = new comefrom("广西", "|南宁|柳州|桂林|梧州|北海|防城港|钦州|贵港|玉林|南宁地区|柳州地区|

贺州|百色|河池");
    where[22] = new comefrom("海南", "|海口|三亚");
    where[23] = new comefrom("四川", "|成都|绵阳|德阳|自贡|攀枝花|广元|内江|乐山|南充|宜宾|广安|达川|雅安

|眉山|甘孜|凉山|泸州");
    where[24] = new comefrom("贵州", "|贵阳|六盘水|遵义|安顺|铜仁|黔西南|毕节|黔东南|黔南");
    where[25] = new comefrom("云南", "|昆明|大理|曲靖|玉溪|昭通|楚雄|红河|文山|思茅|西双版纳|保山|德宏|丽

江|怒江|迪庆|临沧");
    where[26] = new comefrom("西藏", "|拉萨|日喀则|山南|林芝|昌都|阿里|那曲");
    where[27] = new comefrom("陕西", "|西安|宝鸡|咸阳|铜川|渭南|延安|榆林|汉中|安康|商洛");
    where[28] = new comefrom("甘肃", "|兰州|嘉峪关|金昌|白银|天水|酒泉|张掖|武威|定西|陇南|平凉|庆阳|临夏

|甘南");
    where[29] = new comefrom("宁夏", "|银川|石嘴山|吴忠|固原");
    where[30] = new comefrom("青海", "|西宁|海东|海南|海北|黄南|玉树|果洛|海西");
    where[31] = new comefrom("新疆", "|乌鲁木齐|石河子|克拉玛依|伊犁|巴音郭勒|昌吉|克孜勒苏柯尔克孜|博尔

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    where[32] = new comefrom("香港", "");
    where[33] = new comefrom("澳门", "");
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    where[35] = new comefrom("其它", "|北美洲|南美洲|亚洲|非洲|欧洲|大洋洲");
    function select() {
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            var loca2 = options[selectedIndex].value;
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        }
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                        length = loca3.length; options[j].text = loca3[j]; options[j].value = loca3[j];

var loca4 = options[selectedIndex].value;
                        document.getElementById("<%= txt_MemberCity.ClientID%>").value = loca4;
                    }
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    window.onload=function init() {
    var proid = "<%=province.ClientID %>"
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    </script>

    <h2>
        欢迎使用 ASP.
    </h2>
    <p>
        若要了解关于 ASP.NET 的详细信息，请访问 <a href="" title="ASP.NET 网

站">www.asp.net/cn</a>。
    </p>
    <p>
        <tr>
                <td>
                    省份：
                </td>
                <td>
                    <asp:DropDownList ID="province" runat="server" onChange="select()"
                        Width="205px">
                    </asp:DropDownList>
                    <asp:TextBox ID="txt_MemberProvince" runat="server" Style="margin-left: 0px;

border:none"
                        Width="40px"></asp:TextBox>
                </td>
                <td>
                    城市：
                </td>
                <td>
                    <asp:DropDownList ID="city" runat="server" onChange="select()" Width="205px">
                    </asp:DropDownList>
                    <asp:TextBox ID="txt_MemberCity" runat="server" Width="40px" Style="margin-left: 0px;

border:none"></asp:TextBox>
                </td>
            </tr>
        您还可以找到 <a href=""
            title="MSDN ASP.NET 文档">MSDN 上有关 ASP.NET 的文档</a>。
    </p>

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