JavaScript实现城市选择控件的效果

在淘宝旅行上看到的城市选择效果，感觉还不错，就自己的理解重新实现一遍，先看效果（有人说IE9下面有BUG，LZ用的是落后的XP，居然装不上IE9，去公司在搞搞好了），然后再细说实现原理，支持鼠标上下键选择城市，支持直接输入城市名称，拼音首字母，全拼，支持IE6遮盖SELECT，压缩后12K。

实现的步骤：

一、先用一定的格式罗列出控件所需要的城市以及拼音等，我这里是按照如下格式罗列成一个数组, 如果需要增加城市，直接增加在数组里面即可：

城市我是一个一个手打的。。。

['北京|beijing|bj','上海|shanghai|sh', '重庆|chongqing|cq']

二、因为控件的城市分组按好几类划分，比如：按首字母HOT 、ABCDEFH  、  IJKLMNOP  、 QRSTUVWXYZ 四组划分，

而划分了四组后又按照了首字母划分，所以我用正则表达式和循环把数组重新格式化为一个分组对象，热门城市取前16条。

对象格式如下：

{HOT:{hot:[]},ABCDEFGH:{a:[1,2,3],b:[1,2,3]},IJKLMNOP:{i:[1.2.3],j:[1,2,3]},QRSTUVWXYZ:{}}

所用代码如下：

/* *
 * 格式化城市数组为对象oCity，按照a-h,i-p,q-z,hot热门城市分组：
 * {HOT:{hot:[]},ABCDEFGH:{a:[1,2,3],b:[1,2,3]},IJKLMNOP:{i:[1.2.3],j:[1,2,3]},QRSTUVWXYZ:{}}
 * */ 

(function () {
 var citys = Vcity.allCity, match, letter,
  regEx = Vcity.regEx,
  reg2 = /^[a-h]$/i, reg3 = /^[i-p]$/i, reg4 = /^[q-z]$/i;
 if (!Vcity.oCity) {
  Vcity.oCity = {hot:{},ABCDEFGH:{}, IJKLMNOP:{}, QRSTUVWXYZ:{}};
  //console.log(citys.length);
  for (var i = 0, n = citys.length; i < n; i++) {
   match = regEx.exec(citys[i]);
   letter = match[3].toUpperCase();
   if (reg2.test(letter)) {
    if (!Vcity.oCity.ABCDEFGH[letter]) Vcity.oCity.ABCDEFGH[letter] = [];
    Vcity.oCity.ABCDEFGH[letter].push(match[1]);
   } else if (reg3.test(letter)) {
    if (!Vcity.oCity.IJKLMNOP[letter]) Vcity.oCity.IJKLMNOP[letter] = [];
    Vcity.oCity.IJKLMNOP[letter].push(match[1]);
   } else if (reg4.test(letter)) {
    if (!Vcity.oCity.QRSTUVWXYZ[letter]) Vcity.oCity.QRSTUVWXYZ[letter] = [];
    Vcity.oCity.QRSTUVWXYZ[letter].push(match[1]);
   }
   /* 热门城市 前16条 */
   if(i<16){
    if(!Vcity.oCity.hot['hot']) Vcity.oCity.hot['hot'] = [];
    Vcity.oCity.hot['hot'].push(match[1]);
   }
  }
 }
})();

三、然后先照着淘宝旅行里面的样子弄出HTML与CSS；这里略过。

四、然后开始建立CitySelector构造函数，根据城市对象，构建生成DOM对象，在按照相应的事件触发。在生成相应的按照A\B\C\D……分组的时候遇到一个

关于排序的问题，我的对象格式是这样的ABCDEFGH:{a:[1,2,3],b:[1,2,3],c:[1,2,3]},里面的小数组要按照字母的顺序排序，但是我用for……in循环生成

出来是乱的，咨询了群里的高人后，处理方法如下：这里单独把KEY拿出来组成一个数组，然后排序后，在根据数组的值作为KEY值，来读取对象！

sortKey=[];
   for(ckey in oCity[key]){
    sortKey.push(ckey);
    // ckey按照ABCDEDG顺序排序
    sortKey.sort();
   }
   for(var j=0,k = sortKey.length;j<k;j++){
    odl = document.createElement('dl');
    odt = document.createElement('dt');
    odd = document.createElement('dd');
    odt.innerHTML = sortKey[j] == 'hot'?' ':sortKey[j];
    odda = [];
    for(var i=0,n=oCity[key][sortKey[j]].length;i<n;i++){
     str = '<a href="#">' + oCity[key][sortKey[j]][i] + '</a>';
     odda.push(str);
    }

五、鼠标上下键移动选择城市的处理方法：在城市弹出后记录一个this.count = 0；然后再获取上下键的按键事件中分别对count值加一或者减一，

当然count的最大值不能大于筛选出来的城市数组的长度，超过长度后归0，小于0后赋值最大值，然后把this.count的值，来作为数组的标获取相应的城市项：

switch(keycode){
   case 40: //向下箭头↓
    this.count++;
    if(this.count > len-1) this.count = 0;
    for(var i=0;i<len;i++){
     Vcity._m.removeClass('on',lis[i]);
    }
    Vcity._m.addClass('on',lis[this.count]);
    break;
   case 38: //向上箭头↑
    this.count--;
    if(this.count<0) this.count = len-1;
    for(i=0;i<len;i++){
     Vcity._m.removeClass('on',lis[i]);
    }
    Vcity._m.addClass('on',lis[this.count]);
    break;
   case 13: // enter键
    this.input.value = Vcity.regExChiese.exec(lis[this.count].innerHTML)[0];
    Vcity._m.addClass('hide',this.ul);
    Vcity._m.addClass('hide',this.ul);
    /* IE6 */
    Vcity._m.addClass('hide',this.myIframe);
    break;
   default:
    break;
  }

六、IE中对SELECT的遮挡也是一个增加代码的地方，因为城市弹出框的大小是变化的，然后下拉的城市列也是根据筛选出来的值而变化，所以得每操作一个变化的地方的时候就重新给iframe设置长度和宽度，苦逼的处理方法啊，所以就多了这样一个方法，然后在改变尺寸的时候，应用一下就可以了。

/* IE6的改变遮罩SELECT 的 IFRAME尺寸大小 */
 changeIframe:function(){
  if(!this.isIE6)return;
  this.myIframe.style.width = this.rootDiv.offsetWidth + 'px';
  this.myIframe.style.height = this.rootDiv.offsetHeight + 'px';
 }

7、弹出框的取消问题，这个问题最开始我是设置document的click事件关闭层，然后再弹出的层上阻止click事件的冒泡，但是这样两个层有同时出现的可能，

// 设置点击文档隐藏弹出的城市选择框
  Vcity._m.on(document, 'click', function (event) {
   event = Vcity._m.getEvent(event);
   var target = Vcity._m.getTarget(event);
   if(target == that.input) return false;
   //console.log(target.className);
   if (that.cityBox)Vcity._m.addClass('hide', that.cityBox);
   if (that.ul)Vcity._m.addClass('hide', that.ul);
   if(that.myIframe)Vcity._m.addClass('hide',that.myIframe);
  }); 

8、输入框输入拼音或者文字或者拼音首字母筛选城市，这个就是直接用正则表达式在最开始的数组里面筛选数据即可：

var reg = new RegExp("^" + value + "|\\|" + value, 'gi');
   var searchResult = [];
   for (var i = 0, n = Vcity.allCity.length; i < n; i++) {
    if (reg.test(Vcity.allCity[i])) {
     var match = Vcity.regEx.exec(Vcity.allCity[i]);
     if (searchResult.length !== 0) {
      str = '<li><b class="cityname">' + match[1] + '</b><b class="cityspell">' + match[2] + '</b></li>';
     } else {
      str = '<li class="on"><b class="cityname">' + match[1] + '</b><b class="cityspell">' + match[2] + '</b></li>';
     }
     searchResult.push(str);
    }
   }

然后总的JS代码如下：

/* *
 * ---------------------------------------- *
 * 城市选择组件 v1.0
 * Author: VVG
 * QQ: 83816819
 * Mail: mysheller@163.com
 * http://www.cnblogs.com/NNUF/
 * ---------------------------------------- *
 * Date: 2012-07-10
 * ---------------------------------------- *
 * */ 

/* *
 * 全局空间 Vcity
 * */
var Vcity = {};
/* *
 * 静态方法集
 * @name _m
 * */
Vcity._m = {
 /* 选择元素 */
 $:function (arg, context) {
  var tagAll, n, eles = [], i, sub = arg.substring(1);
  context = context || document;
  if (typeof arg == 'string') {
   switch (arg.charAt(0)) {
    case '#':
     return document.getElementById(sub);
     break;
    case '.':
     if (context.getElementsByClassName) return context.getElementsByClassName(sub);
     tagAll = Vcity._m.$('*', context);
     n = tagAll.length;
     for (i = 0; i < n; i++) {
      if (tagAll[i].className.indexOf(sub) > -1) eles.push(tagAll[i]);
     }
     return eles;
     break;
    default:
     return context.getElementsByTagName(arg);
     break;
   }
  }
 }, 

 /* 绑定事件 */
 on:function (node, type, handler) {
  node.addEventListener ? node.addEventListener(type, handler, false) : node.attachEvent('on' + type, handler);
 }, 

 /* 获取事件 */
 getEvent:function(event){
  return event || window.event;
 }, 

 /* 获取事件目标 */
 getTarget:function(event){
  return event.target || event.srcElement;
 }, 

 /* 获取元素位置 */
 getPos:function (node) {
  var scrollx = document.documentElement.scrollLeft || document.body.scrollLeft,
   scrollt = document.documentElement.scrollTop || document.body.scrollTop;
  var pos = node.getBoundingClientRect();
  return {top:pos.top + scrollt, right:pos.right + scrollx, bottom:pos.bottom + scrollt, left:pos.left + scrollx }
 }, 

 /* 添加样式名 */
 addClass:function (c, node) {
  if(!node)return;
  node.className = Vcity._m.hasClass(c,node) ? node.className : node.className + ' ' + c ;
 }, 

 /* 移除样式名 */
 removeClass:function (c, node) {
  var reg = new RegExp("(^|\\s+)" + c + "(\\s+|$)", "g");
  if(!Vcity._m.hasClass(c,node))return;
  node.className = reg.test(node.className) ? node.className.replace(reg, '') : node.className;
 }, 

 /* 是否含有CLASS */
 hasClass:function (c, node) {
  if(!node || !node.className)return false;
  return node.className.indexOf(c)>-1;
 }, 

 /* 阻止冒泡 */
 stopPropagation:function (event) {
  event = event || window.event;
  event.stopPropagation ? event.stopPropagation() : event.cancelBubble = true;
 },
 /* 去除两端空格 */
 trim:function (str) {
  return str.replace(/^\s+|\s+$/g,'');
 }
}; 

/* 所有城市数据,可以按照格式自行添加（北京|beijing|bj），前16条为热门城市 */ 

Vcity.allCity = ['北京|beijing|bj','上海|shanghai|sh', '重庆|chongqing|cq', '深圳|shenzhen|sz', '广州|guangzhou|gz', '杭州|hangzhou|hz',
 '南京|nanjing|nj', '苏州|shuzhou|sz', '天津|tianjin|tj', '成都|chengdu|cd', '南昌|nanchang|nc', '三亚|sanya|sy','青岛|qingdao|qd',
 '厦门|xiamen|xm', '西安|xian|xa','长沙|changsha|cs','合肥|hefei|hf','西藏|xizang|xz', '内蒙古|neimenggu|nmg', '安庆|anqing|aq', '阿泰勒|ataile|atl', '安康|ankang|ak',
 '阿克苏|akesu|aks', '包头|baotou|bt', '北海|beihai|bh', '百色|baise|bs','保山|baoshan|bs', '长治|changzhi|cz', '长春|changchun|cc', '常州|changzhou|cz', '昌都|changdu|cd',
 '朝阳|chaoyang|cy', '常德|changde|cd', '长白山|changbaishan|cbs', '赤峰|chifeng|cf', '大同|datong|dt', '大连|dalian|dl', '达县|daxian|dx', '东营|dongying|dy', '大庆|daqing|dq', '丹东|dandong|dd',
 '大理|dali|dl', '敦煌|dunhuang|dh', '鄂尔多斯|eerduosi|eeds', '恩施|enshi|es', '福州|fuzhou|fz', '阜阳|fuyang|fy', '贵阳|guiyang|gy',
 '桂林|guilin|gl', '广元|guangyuan|gy', '格尔木|geermu|gem', '呼和浩特|huhehaote|hhht', '哈密|hami|hm',
 '黑河|heihe|hh', '海拉尔|hailaer|hle', '哈尔滨|haerbin|heb', '海口|haikou|hk', '黄山|huangshan|hs', '邯郸|handan|hd',
 '汉中|hanzhong|hz', '和田|hetian|ht', '晋江|jinjiang|jj', '锦州|jinzhou|jz', '景德镇|jingdezhen|jdz',
 '嘉峪关|jiayuguan|jyg', '井冈山|jinggangshan|jgs', '济宁|jining|jn', '九江|jiujiang|jj', '佳木斯|jiamusi|jms', '济南|jinan|jn',
 '喀什|kashi|ks', '昆明|kunming|km', '康定|kangding|kd', '克拉玛依|kelamayi|klmy', '库尔勒|kuerle|kel', '库车|kuche|kc', '兰州|lanzhou|lz',
 '洛阳|luoyang|ly', '丽江|lijiang|lj', '林芝|linzhi|lz', '柳州|liuzhou|lz', '泸州|luzhou|lz', '连云港|lianyungang|lyg', '黎平|liping|lp',
 '连成|liancheng|lc', '拉萨|lasa|ls', '临沧|lincang|lc', '临沂|linyi|ly', '芒市|mangshi|ms', '牡丹江|mudanjiang|mdj', '满洲里|manzhouli|mzl', '绵阳|mianyang|my',
 '梅县|meixian|mx', '漠河|mohe|mh', '南充|nanchong|nc', '南宁|nanning|nn', '南阳|nanyang|ny', '南通|nantong|nt', '那拉提|nalati|nlt',
 '宁波|ningbo|nb', '攀枝花|panzhihua|pzh', '衢州|quzhou|qz', '秦皇岛|qinhuangdao|qhd', '庆阳|qingyang|qy', '齐齐哈尔|qiqihaer|qqhe',
 '石家庄|shijiazhuang|sjz', '沈阳|shenyang|sy', '思茅|simao|sm', '铜仁|tongren|tr', '塔城|tacheng|tc', '腾冲|tengchong|tc', '台州|taizhou|tz',
 '通辽|tongliao|tl', '太原|taiyuan|ty', '威海|weihai|wh', '梧州|wuzhou|wz', '文山|wenshan|ws', '无锡|wuxi|wx', '潍坊|weifang|wf', '武夷山|wuyishan|wys', '乌兰浩特|wulanhaote|wlht',
 '温州|wenzhou|wz', '乌鲁木齐|wulumuqi|wlmq', '万州|wanzhou|wz', '乌海|wuhai|wh', '兴义|xingyi|xy', '西昌|xichang|xc', '襄樊|xiangfan|xf',
 '西宁|xining|xn', '锡林浩特|xilinhaote|xlht', '西双版纳|xishuangbanna|xsbn', '徐州|xuzhou|xz', '义乌|yiwu|yw', '永州|yongzhou|yz', '榆林|yulin|yl', '延安|yanan|ya', '运城|yuncheng|yc',
 '烟台|yantai|yt', '银川|yinchuan|yc', '宜昌|yichang|yc', '宜宾|yibin|yb', '盐城|yancheng|yc', '延吉|yanji|yj', '玉树|yushu|ys', '伊宁|yining|yn', '珠海|zhuhai|zh', '昭通|zhaotong|zt',
 '张家界|zhangjiajie|zjj', '舟山|zhoushan|zs', '郑州|zhengzhou|zz', '中卫|zhongwei|zw', '芷江|zhijiang|zj', '湛江|zhanjiang|zj']; 

/* 正则表达式 筛选中文城市名、拼音、首字母 */ 

Vcity.regEx = /^([\u4E00-\u9FA5\uf900-\ufa2d]+)\|(\w+)\|(\w)\w*$/i;
Vcity.regExChiese = /([\u4E00-\u9FA5\uf900-\ufa2d]+)/; 

/* *
 * 格式化城市数组为对象oCity，按照a-h,i-p,q-z,hot热门城市分组：
 * {HOT:{hot:[]},ABCDEFGH:{a:[1,2,3],b:[1,2,3]},IJKLMNOP:{i:[1.2.3],j:[1,2,3]},QRSTUVWXYZ:{}}
 * */ 

(function () {
 var citys = Vcity.allCity, match, letter,
  regEx = Vcity.regEx,
  reg2 = /^[a-h]$/i, reg3 = /^[i-p]$/i, reg4 = /^[q-z]$/i;
 if (!Vcity.oCity) {
  Vcity.oCity = {hot:{},ABCDEFGH:{}, IJKLMNOP:{}, QRSTUVWXYZ:{}};
  //console.log(citys.length);
  for (var i = 0, n = citys.length; i < n; i++) {
   match = regEx.exec(citys[i]);
   letter = match[3].toUpperCase();
   if (reg2.test(letter)) {
    if (!Vcity.oCity.ABCDEFGH[letter]) Vcity.oCity.ABCDEFGH[letter] = [];
    Vcity.oCity.ABCDEFGH[letter].push(match[1]);
   } else if (reg3.test(letter)) {
    if (!Vcity.oCity.IJKLMNOP[letter]) Vcity.oCity.IJKLMNOP[letter] = [];
    Vcity.oCity.IJKLMNOP[letter].push(match[1]);
   } else if (reg4.test(letter)) {
    if (!Vcity.oCity.QRSTUVWXYZ[letter]) Vcity.oCity.QRSTUVWXYZ[letter] = [];
    Vcity.oCity.QRSTUVWXYZ[letter].push(match[1]);
   }
   /* 热门城市 前16条 */
   if(i<16){
    if(!Vcity.oCity.hot['hot']) Vcity.oCity.hot['hot'] = [];
    Vcity.oCity.hot['hot'].push(match[1]);
   }
  }
 }
})();
/* 城市HTML模板 */
Vcity._template = [
 '<p class="tip">热门城市(支持汉字/拼音)</p>',
 '<ul>',
 '<li class="on">热门城市</li>',
 '<li>ABCDEFGH</li>',
 '<li>IJKLMNOP</li>',
 '<li>QRSTUVWXYZ</li>',
 '</ul>'
]; 

/* *
 * 城市控件构造函数
 * @CitySelector
 * */ 

Vcity.CitySelector = function () {
 this.initialize.apply(this, arguments);
}; 

Vcity.CitySelector.prototype = { 

 constructor:Vcity.CitySelector, 

 /* 初始化 */ 

 initialize :function (options) {
  var input = options.input;
  this.input = Vcity._m.$('#'+ input);
  this.inputEvent();
 }, 

 /* *
  * @createWarp
  * 创建城市BOX HTML 框架
  * */ 

 createWarp:function(){
  var inputPos = Vcity._m.getPos(this.input);
  var div = this.rootDiv = document.createElement('div');
  var that = this; 

  // 设置DIV阻止冒泡
  Vcity._m.on(this.rootDiv,'click',function(event){
   Vcity._m.stopPropagation(event);
  }); 

  // 设置点击文档隐藏弹出的城市选择框
  Vcity._m.on(document, 'click', function (event) {
   event = Vcity._m.getEvent(event);
   var target = Vcity._m.getTarget(event);
   if(target == that.input) return false;
   //console.log(target.className);
   if (that.cityBox)Vcity._m.addClass('hide', that.cityBox);
   if (that.ul)Vcity._m.addClass('hide', that.ul);
   if(that.myIframe)Vcity._m.addClass('hide',that.myIframe);
  });
  div.className = 'citySelector';
  div.style.position = 'absolute';
  div.style.left = inputPos.left + 'px';
  div.style.top = inputPos.bottom + 'px';
  div.style.zIndex = 999999; 

  // 判断是否IE6，如果是IE6需要添加iframe才能遮住SELECT框
  var isIe = (document.all) ? true : false;
  var isIE6 = this.isIE6 = isIe && !window.XMLHttpRequest;
  if(isIE6){
   var myIframe = this.myIframe = document.createElement('iframe');
   myIframe.frameborder = '0';
   myIframe.src = 'about:blank';
   myIframe.style.position = 'absolute';
   myIframe.style.zIndex = '-1';
   this.rootDiv.appendChild(this.myIframe);
  } 

  var childdiv = this.cityBox = document.createElement('div');
  childdiv.className = 'cityBox';
  childdiv.id = 'cityBox';
  childdiv.innerHTML = Vcity._template.join('');
  var hotCity = this.hotCity = document.createElement('div');
  hotCity.className = 'hotCity';
  childdiv.appendChild(hotCity);
  div.appendChild(childdiv);
  this.createHotCity();
 }, 

 /* *
  * @createHotCity
  * TAB下面DIV：hot,a-h,i-p,q-z 分类HTML生成，DOM操作
  * {HOT:{hot:[]},ABCDEFGH:{a:[1,2,3],b:[1,2,3]},IJKLMNOP:{},QRSTUVWXYZ:{}}
  **/ 

 createHotCity:function(){
  var odiv,odl,odt,odd,odda=[],str,key,ckey,sortKey,regEx = Vcity.regEx,
   oCity = Vcity.oCity;
  for(key in oCity){
   odiv = this[key] = document.createElement('div');
   // 先设置全部隐藏hide
   odiv.className = key + ' ' + 'cityTab hide';
   sortKey=[];
   for(ckey in oCity[key]){
    sortKey.push(ckey);
    // ckey按照ABCDEDG顺序排序
    sortKey.sort();
   }
   for(var j=0,k = sortKey.length;j<k;j++){
    odl = document.createElement('dl');
    odt = document.createElement('dt');
    odd = document.createElement('dd');
    odt.innerHTML = sortKey[j] == 'hot'?' ':sortKey[j];
    odda = [];
    for(var i=0,n=oCity[key][sortKey[j]].length;i<n;i++){
     str = '<a href="javascript:">' + oCity[key][sortKey[j]][i] + '</a>';
     odda.push(str);
    }
    odd.innerHTML = odda.join('');
    odl.appendChild(odt);
    odl.appendChild(odd);
    odiv.appendChild(odl);
   } 

   // 移除热门城市的隐藏CSS
   Vcity._m.removeClass('hide',this.hot);
   this.hotCity.appendChild(odiv);
  }
  document.body.appendChild(this.rootDiv);
  /* IE6 */
  this.changeIframe(); 

  this.tabChange();
  this.linkEvent();
 }, 

 /* *
  * tab按字母顺序切换
  * @ tabChange
  * */ 

 tabChange:function(){
  var lis = Vcity._m.$('li',this.cityBox);
  var divs = Vcity._m.$('div',this.hotCity);
  var that = this;
  for(var i=0,n=lis.length;i<n;i++){
   lis[i].index = i;
   lis[i].onclick = function(){
    for(var j=0;j<n;j++){
     Vcity._m.removeClass('on',lis[j]);
     Vcity._m.addClass('hide',divs[j]);
    }
    Vcity._m.addClass('on',this);
    Vcity._m.removeClass('hide',divs[this.index]);
    /* IE6 改变TAB的时候 改变Iframe 大小*/
    that.changeIframe();
   };
  }
 }, 

 /* *
  * 城市LINK事件
  * @linkEvent
  * */ 

 linkEvent:function(){
  var links = Vcity._m.$('a',this.hotCity);
  var that = this;
  for(var i=0,n=links.length;i<n;i++){
   links[i].onclick = function(){
    that.input.value = this.innerHTML;
    Vcity._m.addClass('hide',that.cityBox);
    /* 点击城市名的时候隐藏myIframe */
    Vcity._m.addClass('hide',that.myIframe);
   }
  }
 }, 

 /* *
  * INPUT城市输入框事件
  * @inputEvent
  * */ 

 inputEvent:function(){
  var that = this;
  Vcity._m.on(this.input,'click',function(event){
   event = event || window.event;
   if(!that.cityBox){
    that.createWarp();
   }else if(!!that.cityBox && Vcity._m.hasClass('hide',that.cityBox)){
    // slideul 不存在或者 slideul存在但是是隐藏的时候 两者不能共存
    if(!that.ul || (that.ul && Vcity._m.hasClass('hide',that.ul))){
     Vcity._m.removeClass('hide',that.cityBox); 

     /* IE6 移除iframe 的hide 样式 */
     //alert('click');
     Vcity._m.removeClass('hide',that.myIframe);
     that.changeIframe();
    }
   }
  });
  Vcity._m.on(this.input,'focus',function(){
   that.input.select();
   if(that.input.value == '城市名') that.input.value = '';
  });
  Vcity._m.on(this.input,'blur',function(){
   if(that.input.value == '') that.input.value = '城市名';
  });
  Vcity._m.on(this.input,'keyup',function(event){
   event = event || window.event;
   var keycode = event.keyCode;
   Vcity._m.addClass('hide',that.cityBox);
   that.createUl(); 

   /* 移除iframe 的hide 样式 */
   Vcity._m.removeClass('hide',that.myIframe); 

   // 下拉菜单显示的时候捕捉按键事件
   if(that.ul && !Vcity._m.hasClass('hide',that.ul) && !that.isEmpty){
    that.KeyboardEvent(event,keycode);
   }
  });
 }, 

 /* *
  * 生成下拉选择列表
  * @ createUl
  * */ 

 createUl:function () {
  //console.log('createUL');
  var str;
  var value = Vcity._m.trim(this.input.value);
  // 当value不等于空的时候执行
  if (value !== '') {
   var reg = new RegExp("^" + value + "|\\|" + value, 'gi');
   var searchResult = [];
   for (var i = 0, n = Vcity.allCity.length; i < n; i++) {
    if (reg.test(Vcity.allCity[i])) {
     var match = Vcity.regEx.exec(Vcity.allCity[i]);
     if (searchResult.length !== 0) {
      str = '<li><b class="cityname">' + match[1] + '</b><b class="cityspell">' + match[2] + '</b></li>';
     } else {
      str = '<li class="on"><b class="cityname">' + match[1] + '</b><b class="cityspell">' + match[2] + '</b></li>';
     }
     searchResult.push(str);
    }
   }
   this.isEmpty = false;
   // 如果搜索数据为空
   if (searchResult.length == 0) {
    this.isEmpty = true;
    str = '<li class="empty">对不起，没有找到数据 "<em>' + value + '</em>"</li>';
    searchResult.push(str);
   }
   // 如果slideul不存在则添加ul
   if (!this.ul) {
    var ul = this.ul = document.createElement('ul');
    ul.className = 'cityslide';
    this.rootDiv && this.rootDiv.appendChild(ul);
    // 记录按键次数，方向键
    this.count = 0;
   } else if (this.ul && Vcity._m.hasClass('hide', this.ul)) {
    this.count = 0;
    Vcity._m.removeClass('hide', this.ul);
   }
   this.ul.innerHTML = searchResult.join(''); 

   /* IE6 */
   this.changeIframe(); 

   // 绑定Li事件
   this.liEvent();
  }else{
   Vcity._m.addClass('hide',this.ul);
   Vcity._m.removeClass('hide',this.cityBox); 

   Vcity._m.removeClass('hide',this.myIframe); 

   this.changeIframe();
  }
 }, 

 /* IE6的改变遮罩SELECT 的 IFRAME尺寸大小 */
 changeIframe:function(){
  if(!this.isIE6)return;
  this.myIframe.style.width = this.rootDiv.offsetWidth + 'px';
  this.myIframe.style.height = this.rootDiv.offsetHeight + 'px';
 }, 

 /* *
  * 特定键盘事件，上、下、Enter键
  * @ KeyboardEvent
  * */ 

 KeyboardEvent:function(event,keycode){
  var lis = Vcity._m.$('li',this.ul);
  var len = lis.length;
  switch(keycode){
   case 40: //向下箭头↓
    this.count++;
    if(this.count > len-1) this.count = 0;
    for(var i=0;i<len;i++){
     Vcity._m.removeClass('on',lis[i]);
    }
    Vcity._m.addClass('on',lis[this.count]);
    break;
   case 38: //向上箭头↑
    this.count--;
    if(this.count<0) this.count = len-1;
    for(i=0;i<len;i++){
     Vcity._m.removeClass('on',lis[i]);
    }
    Vcity._m.addClass('on',lis[this.count]);
    break;
   case 13: // enter键
    this.input.value = Vcity.regExChiese.exec(lis[this.count].innerHTML)[0];
    Vcity._m.addClass('hide',this.ul);
    Vcity._m.addClass('hide',this.ul);
    /* IE6 */
    Vcity._m.addClass('hide',this.myIframe);
    break;
   default:
    break;
  }
 }, 

 /* *
  * 下拉列表的li事件
  * @ liEvent
  * */ 

 liEvent:function(){
  var that = this;
  var lis = Vcity._m.$('li',this.ul);
  for(var i = 0,n = lis.length;i < n;i++){
   Vcity._m.on(lis[i],'click',function(event){
    event = Vcity._m.getEvent(event);
    var target = Vcity._m.getTarget(event);
    that.input.value = Vcity.regExChiese.exec(target.innerHTML)[0];
    Vcity._m.addClass('hide',that.ul);
    /* IE6 下拉菜单点击事件 */
    Vcity._m.addClass('hide',that.myIframe);
   });
   Vcity._m.on(lis[i],'mouseover',function(event){
    event = Vcity._m.getEvent(event);
    var target = Vcity._m.getTarget(event);
    Vcity._m.addClass('on',target);
   });
   Vcity._m.on(lis[i],'mouseout',function(event){
    event = Vcity._m.getEvent(event);
    var target = Vcity._m.getTarget(event);
    Vcity._m.removeClass('on',target);
   })
  }
 }
};

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