Duele tanto que encapsula una ciudad secundaria y primero me aseguro de que haya un HTML.
<Span style = "fondo de fondo: #ffffff; color: #ff0000"> <select id = "provincia" size = 1> </ectele> <select id = "ciudad"> </select> <input type = "Hidden" id = "pro_city"/> </span>
Luego consulte JS y finalmente lo llama a través de New SelectCity (). Soy demasiado vago para separarme aquí, así que lo escribí en la página
No cierre el código
<html> <fead> <meta charset = "utf-8"> </head> <body> <select id = "provincia" size = 1> </elect> <select id = "ciudad"> </ectele> <input type = "hidden" id = "pro_city"/> <script type = "text/javaScript"> function selectcity () {this.init ();;;;;;;; } SelectCity.prototype = {init: function () {this.arr = new Array (); this.proarr = ['beijing', 'shanghai', 'tianjin', 'chongqing', 'hebei', 'shanxi', 'interior Mongolia ',' Liaoning ',' Jilin ',' Heilongjiang ',' Jiangsu ',' Zhejiang ',' Anhui ',' Fujian ',' Jiangxi ',' Shandong ',' Henan ',' Hubei ',' Huna n ',' guangdong ',' guangxi ',' hainan ',' sichuan ',' guizhou ',' yunnan ',' yansu ',' shaanxi ',' gansu ',' ningxia ',' qinghai ',' xinjiang ',' hong Kong ',' macau ',' taiwan '] this.arr [0] = "dongcheng, xicheng, chongwen, xuanwu, chaoyang, fengtai, shijingshan, haidian, mentougou, fangshan, tongzhou, shunyi, canging, daxing, pinggu, huairou, miyun, yanqing"; this.arr [1] = "Huangpu, Luwan, Xuhui, Changning, Jing'an, Putuo, Zhabei, Hongkou, Yangpu, Minhang, Baoshan, Jiading, Pudong, Jinshan, Songjiang, Qingpu, Nanhui, Fengxian, Chongming"; this. this. Chengkou, Fengdu, Dianjiang, Wulong, Zhongxian, Kaixian, Yunyang, Fengjie, Wushan, Wuxi, Shizhu, Xiushan, Yoyang, Pengshui, Jiangjin, Hechuan, Yongchuen, Nanchuan "; this.arr [4] = "Shijiazhuang, Handan, Xingtai, Baoding, Zhangjiakou, Chengde, Langfang, Tangshan, Qinhuangdao, Cangzhou, Hengshui"; this.arr [5] = "Taiyuan, Datong, Yangquan, Changzhi, Jincheng, Shuozhou, Luliang, Xinzhou, Jinzhong, Linfen, Yuncheng"; this.arr [6] = "Hohhot, Baotou, Wuhai, Chifeng, Hulunbuir League, Alxa League, Zhelim League, Xing'an League, Ulanqab League, Xilingol League, Bayannur League, Yikezhao League"; this.arr [7] = "Shenyang, Dalian, Anshan, Fushun, Benxi, Dandong, Jinzhou, Yingkou, Fuxin, Liaoyang, Panjin, Tieling, Chaoyang, Huludao"; this.arr [8] = "Changchun, Jilin, Siping, Liaoyuan, Tonghua, Baishan, Songyuan, Baicheng, Yanbian"; this.arr [9] = "Harbin, Qiqihar, Mudanjiang, Jiamusi, Daqing, Suihua, Hegang, Jixi, Heihe, Shuangyashan, Yichun, Qitaihe, Daxinganling"; this.arr [10] = "Nanjing, Zhenjiang, Suzhou, Nantong, Yangzhou, Yancheng, Xuzhou, Lianyungang, Changzhou, Wuxi, Suqian, Taizhou, Huai'an"; this.arr [11] = "Hangzhou, Ningbo, Wenzhou, Jiaxing, Huzhou, Shaoxing, Jinhua, Quzhou, Zhoushan, Taizhou, Lishui"; esto this.arr [13] = "Fuzhou, Xiamen, Putian, Sanming, Quanzhou, Zhangzhou, Nanping, Longyan, Ningde"; this. this.arr [15] = "Jinan, Qingdao, Zibo, Zaozhuang, Dongying, Yantai, Weifang, Jining, Tai'an, Weihai, Rizhao, Laiwu, Linyi, Dezhou, Liaocheng, Binzhou, Haze"; this.arr [16] = "Zhengzhou, Kaifeng, Luoyang, Pingdingshan, Anyang, Hebi, Xinxiang, Jiaozuo, Puyang, Xuchang, Luohe, Sanmenxia, Nanyang, Shangqiu, Xinyang, Zhoukou, Zhumadian, Jiyuan"; this.arr [17] = "Wuhan, Yichang, Jingzhou, Xiangfan, Huangshi, Jingmen, Huanggang, Shiyan, Enshi, Qianjiang, Tianmen, Xiantao, Suizhou, Xianning, Xiaogan, Ezhou"; this.arr [18] = "Changsha, Changde, Zhuzhou, Xiangtan, Hengyang, Yueyang, Shayang, Yiyang, Loudi, Huaihua, Chenzhou, Yongzhou, Xiangxi, Zhangjiajie"; this.arr [19] = "Guangzhou, Shenzhen, Zhuhai, Shantou, DongGuan, Zhongshan, Foshan, Shaoguan, Jiangmen, Zhanjiang, Maoming, Zhaoqing, Huizhou, Meizhou, Shanwei, Heyuan, Yangjiang, Qingyuan, Cheyang, Jayang, Cheyang, Cheyang, Cheyange, Cheyang, Cheyang, Cheyang, Cheyang, Jayang, Cheyang, Cheyang, Cheyang, Cheyang, Cheyang, Cheyang, Jayange, Cheyange, Cheyange, Cheyange, Jayange, Cheyange, Jayange, Cheyang, Cheyang, Jayange, Jayange, Jayange, Jayange, Jayange, Jayange, Jayange, Cheyang, Cheyan Yunfu "; this.arr [20] = "Nanning, Liuzhou, Guilin, Wuzhou, Beihoi, Fangchenggang, Qinzhou, Guigang, Yulin, región de Nanning, región de Liuzhou, Hezhou, Baise, Hechi"; this.arr [21] = "Haikou, Sanya"; this.arr [22] = "Chengdu, Mianyang, Deyang, Zigong, Panzhihua, Guangyuan, Neijiang, Leshan, Nanchong, Yibin, Guang'an, Dachuan, Ya'an, Meishan, Ganzi, Liangshan, Luzhou"; this.arr [23] = "Guiyang, Liupanshui, Zunyi, Anshun, Tongren, Southwest Guizhou, Bijie, Sudeste de Guizhou"; this.arr [24] = "Kunming, Dali, Qujing, Yuxi, Zhaotong, Chuxiong, Honhe, Wenshan, Simao, Xishuangbanna, Baoshan, Dehong, Lijiang, Nujiang, Diqing, Lincang"; this.arr [25] = "Lhasa, Shigatse, Shannan, Linzhi, Changdu, Ali, Naqu"; this.arr [26] = "Xi'an, Baoji, Xianyang, Tongchuan, Weinan, Yan'an, Yulin, Hanzhong, Ankang, Shangluo"; this.arr [27] = "Lanzhou, Jiayuguan, Jinchang, Baiyin, TiAnshui, Jiuquan, Zhangye, Wuwei, Dingxi, Longnan, Pingliang, Qingyang, Linxia, Gannan"; this.arr [28] = "Yinchuan, Shizuishan, Wuzhong, Guyuan"; this.arr [29] = "Xining, Haidong, Hainan, Haibei, Huangnan, Yushu, Goluo, Haixi"; this.arr [30] = "Urumqi, Shihezi, Karamay, Yili, Bayingol, Changji, Kizilsu Kirgiz, Bortala, Turpan, Hami, Kashgar, Hotan, Aksu"; this.arr [31] = "Hong Kong"; this.arr [32] = "Macao"; this. var city = document.getElementById ("ciudad"); var cityarr = this.arr [0] .split (","); var pro = document.getElementById ("provincia"); // Inicializar la provincia de Beijing para (var i = 0; i <this.proarr.length; i ++) {pro [i] = nueva opción (this.proarr [i], this.proarr [i]); } // Inicializar la ciudad de Beijing para (var i = 0; i <cityarr.length; i ++) {ciudad [i] = nueva opción (Cityarr [i], Cityarr [i]); } this.handelEvent (); }, HandelEvent: function () {var _this = this; //alert(THIS.Arrche20]) var pro = document.getElementById ("provincia"); var city = document.getElementById ("ciudad"); var pro_city = document.getElementById ('pro_city'); pro.onchange = function () {var index = this.selectedIndex; var cityarr = _this.arr [index] .split (","); City.length = 0; // llena los valores en la matriz de la ciudad en el cuadro desplegable de la ciudad para (var i = 0; i <cityarr.length; i ++) {ciudad [i] = nueva opción (Cityarr [i], cityarr [i]); }} city.onchange = function () {// Escribe el valor final en una entrada oculta para personalizar el formato pro_city.value = pro.value+'-'+this.value; alert (pro_city.value)}}} new SelectCity (); </script> </body> </html>Lo anterior es todo el contenido del código de implementación de la lista desplegable de la ciudad de segundo nivel encapsulada de JS nativa presentada por el editor. Espero que todos apoyen más a los pasos a casa.