function setcity(city) {
    switch (document.form1["Sheng_Name"].value) {

        case "1" :
            var cityOptions = new Array(

            "杭州", "1",
            "湖州", "2",
            "嘉兴", "3",
            "宁波", "4",
            "台州", "5",
            "衢州", "6",
            "金华", "7",
            "乐清", "8",
            "温州", "9",
            "丽水", "10",
            "临安", "11",
            "绍兴", "24","");
            break;

        case "2" :
            var cityOptions = new Array(

            "南京", "26",
            "徐州", "28",
            "无锡", "29",
            "连云港市", "30",
            "苏州", "31",
            "常州", "32",
            "南通", "33",
            "宿迁", "34",
            "镇江", "35",
            "盐城", "36","");
            break;

        case "3" :
            var cityOptions = new Array(

            "合肥", "25",
            "芜湖", "37",
            "蚌埠", "38",
            "淮南", "39",
            "马鞍山", "40",
            "淮北", "41",
            "铜陵", "42",
            "黄山", "43","");
            break;

        case "4" :
            var cityOptions = new Array(
"");
            break;

        case "5" :
            var cityOptions = new Array(
"");
            break;

        case "6" :
            var cityOptions = new Array(
"");
            break;

        case "7" :
            var cityOptions = new Array(

            "桂林", "16",
            "百色", "17",
            "柳江", "18",
            "南宁", "19",
            "北海", "20",
            "钦州", "21",
            "阳朔", "22",
            "玉林", "23","");
            break;

        case "8" :
            var cityOptions = new Array(
"");
            break;

        case "9" :
            var cityOptions = new Array(
"");
            break;

        case "10" :
            var cityOptions = new Array(
"");
            break;

        case "11" :
            var cityOptions = new Array(

            "哈尔滨", "12",
            "牡丹江", "13",
            "大兴安岭", "14","");
            break;

        case "12" :
            var cityOptions = new Array(
"");
            break;

        case "13" :
            var cityOptions = new Array(
"");
            break;

        case "14" :
            var cityOptions = new Array(
"");
            break;

        case "15" :
            var cityOptions = new Array(
"");
            break;

        case "16" :
            var cityOptions = new Array(
"");
            break;

        case "17" :
            var cityOptions = new Array(
"");
            break;

        case "18" :
            var cityOptions = new Array(
"");
            break;

        case "19" :
            var cityOptions = new Array(
"");
            break;

        case "20" :
            var cityOptions = new Array(
"");
            break;

        case "21" :
            var cityOptions = new Array(
"");
            break;

        case "22" :
            var cityOptions = new Array(
"");
            break;

        case "23" :
            var cityOptions = new Array(
"");
            break;

        case "24" :
            var cityOptions = new Array(
"");
            break;

        case "25" :
            var cityOptions = new Array(
"");
            break;

        case "26" :
            var cityOptions = new Array(
"");
            break;

        case "27" :
            var cityOptions = new Array(
"");
            break;

        case "28" :
            var cityOptions = new Array(
"");
            break;

        default:
            var cityOptions = new Array("", "");
            break;
    }
	
	document.form1["City_Name"].options.length = 0;
	for(var i = 0; i < cityOptions.length/2-1; i++) {
	    document.form1["City_Name"].options[i]=new Option(cityOptions[i*2],cityOptions[i*2+1]);

	    if (document.form1["City_Name"].options[i].value==city) 
	    {
	    	document.form1["City_Name"].selectedIndex = i;
	    }
	}
	document.form1["City_Name"].selectedIndex =0;
}